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"Leeroy Jenkins created a strategy that revolved around trying to defeat your opponent in one turn without requiring any cards on the board. Fighting for board control and battles between minions make an overall game of Hearthstone more fun and compelling, but taking 20+ damage in one turn is not particularly fun or interactive."

Balance is a bit of touchy issue in Hearthstone. On average you'll have one guy hollering for nerfs on, say, Harvest Golem and the next guy will be explaining why that would be a terrible idea. The stuff on this page, on the other hand? These are broken. These cards have, at one point or another, forced the meta to adapt to it significantly like no card should be allowed to, to much derision.


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  • Life Tap, the Warlock hero power, allows him to draw a card at a cost of 2 mana and 2 health, meaning that a well-built Warlock deck can eliminate the need for card draw, save their card slots for other card options and offers the Warlock discounts for 8/8 powerhouses like Mountain Giant and Molten Giant. Notably, whereas most of the exploitable stuff in Hearthstone gains a counter or ends up nerfed, Life Tap simply got better over time with the release of better healing cards like Antique Healbot and Reno Jackson. Life Tap is good enough that for the longest time their exclusive cards were deliberately designed to be middle-of-the-road in terms of use, which makes the rare times where they get powerful stuff hurt much, much more.
  • The Charge keyword. Any minion with Charge attached sacrifices a lot of stat points in exchange for the ability to attack immediately. It sounds fine at first, because after all a minion with Charge is no different than a damaging spell, and sometimes they're less efficient as well (compare the 3 mana 3-1 Charge Wolfrider to the 2 mana deal 3 damage Darkbomb for example). There's two key differences: Chargers are minions, meaning that the opponent has to go through the effort of removing them, meaning that aggro decks can use them to reliably go for the face because their opponent will need to use resources to kill it, leaving the aggro player with the advantage. The other, more significant problem is that Chargers can be buffed by spells and other minions, allowing for some crazy high-damage combos. Blizzard themselves have admitted that they underestimated the power of Charge, and since launch have done a much better job of balancing the mechanic.
    • They went so far as to create a "fixed" version of Charge in The Witchwood; Rush, which is identical to Charge except it can only hit minions on the turn they're played. This allowed the team to create minions with fast, spell-like effects and not worry about it being used to SMOrc the opponent.
  • Silence, a very rare card mechanic that removes all text and buffs from a minion. Silence's goal was true and noble, being intended to prevent other, much more dangerous cards like the later mentioned Tirion Fordring and Savannah Highmane from tearing the game apart, but unfortunately that didn't work out. In practice, Silence neutralized a significant chunk of the game's cards, including ones with unique mechanics that never saw the light of day because of it, and was ruthlessly abused to push Taunt minions out of the way to get a previously prevented lethal. It was so annoying that when the Whispers of the Old Gods nerfs came around, it targeted the two main Silence cards, Ironbeak Owl and Keeper of the Grove, with extreme prejudice.
  • "Curvestone", a derogatory term for a deck strategy based around simply dropping the most cost-efficient minion each turn and outvaluing the enemy until they die. By pumping out as many stats as possible per turn, the opponent will eventually fail to have the necessary removal or board clear to keep Curvestoners from snowballing - and since these decks are based around optimizing board control until they're ready to go for the kill, healing cards, Taunts, or even the majority of playable minions won't be of much help. The worst decks of this sort usually have sticky minions as well, giving them more efficient trades and preparing their board for potent buffs. The effectiveness of Curvestone pretty much always depends on the universal quality of removal at the time (a deck with plenty of board wipes and removal will likely slaughter it), but sometimes even that doesn't work if their ability to vomit stats exceeds the enemy's ability to destroy minions.
  • Combosnote  are much stronger here than in other card games. Hearthstone offers no way to play the game during your opponent's turn outside of Secrets, meaning that combos can be done uninterrupted to win the game right there. Additionally, up until Dirty Rat was added in Mean Streets of Gadgetzan, there were no cards that could discard your opponent's cards, meaning they had nothing to fear before the combo dropped. While the nature of combos can vary from deck to deck (such as, say, summoning a particularly strong board or dealing a huge amount of damage, if not an OTK), the jist is largely the same between them - either you kill them before their game-plan comes together, or you don't play fast enough and they just demolish you. A combo deck's power usually depends on consistency, speed, and survivability above all else, but if they pack all three of those, you're in for pain.
  • Hero Cards. They're game-warping Legendaries that replace your hero with a better one, providing a one-time powerful Battlecry (and sometimes a permanent passive effect) and granting you a new Hero Power. While the Battlecry is often important, the Hero Power is the truly broken bit, giving the player something ridiculous that can be done consistently every turn. This means the earlier a Hero Card is drawn, the stronger it is. Matches where both players use them often comes down to whoever draws their's first. Of the twelve introduced at the time of writing, ten have seen top-level competitive play at one point or another and all of them have been meta-busters. While some are more broken than others (see the Knights of the Frozen Throne section below for that), the impact they've had on the game is undeniable.



  • The many, many Aviana + Kun combo decks. Both were never star cards in Standard, but became absolutely disgusting combo pieces when combined. The combo was very simple: draw Aviana and Kun alongside whatever combo cards you needed (Brann, C'thun, Togwaggle, Ixlid, Malygos, Star Aligner, whatever), play Aviana + Kun, then enjoy being able to summon as many minions as you want and have mana to spare for spells. That would just be a regular, slow combo deck, but the backbone on Druid was ridiculous. They had the best card draw, armor gain, and mana ramp in the game. It was common to see a druid with 30 armor who was 5 mana ahead of his opponent. It outpaced combo, combo'd out control, and survived aggro and tempo. Aviana was bumped to 10 mana, but that only required the Druid to also run Innervate. The archetype only became beatable when Wild Growth and Nourish were both nerfed.


  • The Naxxramas-era Deathrattle Hunter. This was a hyper-charged Face Hunter deck that employed Undertaker. Alongside having the most broken 1-drop ever printed, the deck made use of multiple powerful Deathrattle minions from both Naxx and later GvG, many of them game breakers in their own right. Even if Undertaker wasn't drawn, it was still a solid aggro deck. There was zero risk and all reward, which also meant that the deck was stupid easy to play. The deck lasted for almost a year before Undertaker was mercifully nerfed, although the Face Hunter it spawned lingers on.


  • Beta Freeze Mage, a strong candidate for the best deck of all time. While Freeze Mage existed up until Ice Lance was Hall of Famed, it was never so broken as the first public release. It had excellent card draw, high survivability with Ice Block and Ice Barrier, and a devastating burst combo using Fireballs, Frostbolts, and Ice Lances. The whole deck worked like an impeccable machine of efficiency and was nearly unbeatable. What made this so devastating was the low power level of the Classic set. Healing and armor gain were weak, and among most decks it was a game of minion vs. minion incremental value. To make things even crazier, an oversight/bug caused Alexstrasza to remove the target's armor, meaning not even Control Warrior was safe. This eventually led to Blizzard, Cone of Cold, and Frost Nova all going up by one mana before the game launched.


  • Secret Paladin, the scourge of ladder in 2015. People mainly know it for Mysterious Challenger (see below for that card). It was an aggro deck with huge value plays - namely, Mysterious Challenger would pull a Christmas tree of secrets, creating a insane value for free. And they could do it twice. Of course, while Mysterious Challenger was the centerpiece of the deck, it only worked because of all the other broken cards that carried it. Muster For Battle, Shielded Minibot, and Knife Juggler formed an aggressive and extremely efficient early game, Secretkeeper turned those dead draw secrets into bonus stats, and Dr. Boom and Tirion Fordring created a ridiculous mid to late game. Having an absurd power-play on 6 was just the kicker. To boot, when Naxx and GvG rotated out, Secret Paladin disappeared even though Challenger and most of the secrets were still in Standard. Regardless, it remains a niche but existing aggro deck in Wild to this day.
  • The Odd/Even mechanic from The Witchwood was a smashing success (for better or for worse) and spawned many powerful archetypes. But none were as busted as the launch version of Even Paladin. It took the skeleton of the existing zoo-y Silver Hand Paladin from K&C, added the high consistency guaranteed Hero Powers on turn 1 gave them, and broke the game with Call to Arms. That card was already an undercosted board flooding deck-thinner, but Even Paladin's restriction meant it couldn't pull 1-mana minions, summoning 6 mana to the field and effectively removing three bad draws as they moved out of the early game. If a Paladin got this off on turn 3 or 4, it was basically game over. Call to Arms was swiftly nerfed to 5 mana and the aggro spot was overtaken by Odd Paladin, but nothing was ever quite as overpowered as this deck.





  • There is a cautionary tale to giving too many high-power cards to a class all at once. Warlocks had been struggling throughout the Year of the Mammoth, so Blizzard decided to give them a bump in Kobolds & Catacombs. Enter Cubelock. This was a deck that combined control and combo gameplay, and was unrivaled in either spot. It used Doomguards to rush down the opponent, skipping its drawback by cheating it out. It could then be duplicated by Carnivorous Cube, Faceless Manipulator and Prince Taldaram. It also beat aggro decks with Voidlord, which could be summoned as early as turn 5. The main draw was the synergy between Possessed Lackey and Skull of the Man'ari - they were cards that summoned demons for free from the deck or hand respectively. The deck had great consistency, with many of their cards serving multiple purposes and few ways to 'whiff'. Deathrattle synergies worked on both Possessed Lackey and Carnivorous Cube, and the Cube could be used as a deathrattle trigger itself. It didn't matter if you did or didn't draw your demons, since you had contingencies. The deck also boasted incredible healing from Lesser Amethyst Spellstone, Bloodreaver Gul'dan's hero power, and Dark Pact. Even if you somehow made it through their onslaught, Bloodreaver Gul'dan showed up to summon a wall of taunts, or maybe a few Doomguards to outright kill you instead. The deck was hit with two massive nerfs, but still stayed around in Standard until the rotation.


  • Patron Warrior is one of the most infamous decks in the game's history, and for good reason. It was a Tempo/Combo deck that utilized the ridiculous synergy between Grim Patron, Frothing Berserker, and Warsong Commander. The idea was to play the Warsong (whose original effect granted minions with 3 or less Attack Charge), play the Patron and the Berserker, then feed the Berserker by maximizing damage with Charging and multiplying Patrons and various cheap self-damaging effects like Whirlwind, Death's Bite, and Inner Rage. Since the Warsong worked via an enchantment rather than an aura, it allowed the Berserker to attack no matter how much Attack it gained. If executed properly, the Warrior could deal upwards of 40 damage in a single turn. Granted, it was actually really hard to execute it properly, but that didn't stop the deck from flooding the ladder and creating tonnes of uninteractive losses. Eventually Warsong Commander was infamously nerfed to oblivion, but that only lowered the deck from ridiculously busted to really good. For reference, it not only won a tournament in its nerfed state, but it's still a viable deck in Wild.

    Nerfed Cards 
By definition, any card that has ever been nerfed was probably too strong for its own good. If you need a benchmark to compare the power of certain cards, look here.

Post-Release Nerfs

  • Starving Buzzard was a 2 mana 2/1 Hunter Beast that drew a card whenever a Beast was summoned. When combined with Unleash the Hounds, it was a 4 mana combo that drew 1-6 cards with more than enough mana to spare to brutalize the opponent with the extra combo pieces. Buzzard ended up showing Blizzard that Hunter should never be allowed to have card draw ever lest something like this happen again, and it was ruthlessly changed to a 5 mana 3/2.
  • Speaking of Unleash the Hounds, it was a 2 mana (initially 4) Hunter spell that summoned 1/1 Hounds with charge for every enemy minion. The idea was to give Hunters a different style of board clear than other classes, but in practice it just meant that face really was the place. Indeed, playing too many minions against a Hunter could spell death, as Unleash combo-ed very well with most of Hunter's arsenal to increase the damage even further (Timber Wolf, Leokk from Animal Companion), or draw so many cards that winning would be effortless (Starving Buzzard). It was later nerfed to 3 mana.
  • When the game first launched, Warsong Commander was 3 mana 2/3 that gave all friendly minions Charge. After an Awesome, but Impractical setup involving Molten Giants and Youthful Brewmasters came to light, Blizzard realized she might become a serious problem later on, so while the then current combo was fairly weak she might rip the game in half later on, and as such she was nerfed to only grant Charge to minions with 3 or less attack. Their original fears unfortunately came true with the release of Blackrock Mountain, which brought the notoriously overpowered Patron Warrior deck into the game. The deck was focused around granting Charge to the Frothing Berserker and the then new Grim Patron to smash the opponent for buckets of damage or clear the board respectively. Almost nothing could stand against it, and as a result Warsong Commander was neutered to a 3 mana 2/3 that gives all friendly minions with Charge +1 attack, completely erasing her original function.
  • Undertaker, from Curse of Naxxramas. It used to be a 1/2 for 1 mana that gained +1/+1 every time a friendly minion with deathrattle was summoned. A simple concept that was heinously broken by a couple of factors; Naxxramas, the expansion that introduced him into the game, brought with it a ton of cheap deathrattle minions like Haunted Creeper and Webspinner, which combined with the similarly cheap Leper Gnome meant that buffing Undertaker in early turns was laughably easy, and could only snowball out of control from there. More importantly was that if Undertaker died early, it didn't matter. Unlike most of the cards here, you didn't have to tailor your deck for Undertaker; all the cards that activated him were good cards in their own right, and as such your deck quality didn't have to suffer simply to accommodate him. There was zero risk and all reward, which also meant that the decks were stupid easy to play. Undertaker's reign of terror lasted for half a year, until a well deserved nerf arrived that made so that he no longer gained health, which was the first nerf to a card outside of the classic set, and the only one at that until the One Night in Karazhan nerfs.
  • Leeroy Jenkins used to be 6/2 with Charge for 4 mana that summoned 2 1/1 Whelps for his opponent. On top of the downside straight up not mattering if he is used to end the game, his damage-to-mana ratio is equivalent to Fireball, one of the most efficient damage spells in the game. This is without getting into his status as the win condition of Miracle Rogue, which was the reason he had to be nerfed in the first place. Basically, after a Miracle Rogue was done drawing all their cards with Gadgetzan Auctioneer, they would summon Leeroy, attack, and then bring him back to their hand with Shadowstep, not only allowing them to use him again but it decreases his cost by 2, meaning that there was still mana leftover to do whatever they wanted. It wasn't just Miracle Rogue that ran him though- Combo Warlocks, Druids, Aggro Hunters, most decks ran Leeroy even if they couldn't use him to his full potential because he was just that freaking good. He was later nerfed to 5 mana, which reduced his usage but kept him a viable Aggro finisher.
  • Gadgetzan Auctioneer, a 5 mana 4/4 that draws a card whenever the owner casts a spell. It was (and still is, post-nerf) a key piece of Miracle Rogue, a deck based on drawing their deck in one turn with cheap spells to unleash a hellscape of pain on their opponent using Leeroy Jenkins, Questing Adventurer, Edwin VanCleef, or just about anything they could get their hands on. Auctioneer was changed to 6 mana in the Goblins Vs. Gnomes update, which neutered him right up until League of Explorers came along, when the addition of Tomb Pillager brought Miracle Rogue and him back in a much more balanced state.

Whispers of the Old Gods Nerfs

  • On their own, Force of Nature and Savage Roar were pretty reasonable Druid cards. The former was a 6 mana spell that summons 3 2/2 Treants with Charge that die at the end of the turn, the latter is a 3 mana spell that grants all friendly characters +2 attack. Combined, however, you had an absurdly powerful 14 damage, 2 card combo that was run in every single Druid deck. The main problem with the combo was that even though it was no worse than say a double Fireball from a Mage or Cruel Taskmaster+Grommash combo from Warrior, this combo actually scaled with the Druid's board state, as every minion on the board added an additional 2 damage to the combo. Adding to this, the combo was highly flexible, i.e. you could use it in case you needed to kill a big minion or multiple smaller minions. Finally, there's the Double Combo, which is the previous combo with Innervate and another Savage Roar added in, bringing up the minimum damage to 22. The Standard update removed this combo from the game, by changing Force of Nature to a 5-mana spell that simply summons 3 2/2 Treants.
  • Ancient of Lore was a 7 mana 5/5 Druid minion that could either draw 2 cards or restore 5 health. Druid card draw spells usually draw quite a few cards, but are pretty expensive, meaning Druids would normally have to give up a turn just to reload their hand. Ancient of Lore solved this issue handily, allowing them to drop a tough minion in the same turn they draw, and it synergized with Mana acceleration spells like Innervate and Wild Growth to regain the lost card advantage used to summon the Ancient. The health gain, while weak compared to the draw option, was still very handy in aggressive match-ups, restoring life and dropping a body in the process. Finally, the exquisite card draw helped Druids search their deck for the aforementioned Force of Nature+Savage Roar combo, and added several points of damage to it should it survive, making him completely outclass the other draw option for Druid like Nourish. Ancient of Lore was nerfed to only draw 1 card instead, gutting its utility.
  • Blade Flurry was a 2 mana Rogue spell that destroyed their weapon and dealt its damage to all enemies. Combined with weapon buffing cards like Tinker's Sharpsword Oil, Blade Flurry was one of the most powerful sources of burst damage in the entire game that doubled as an incredible board clearing effect, and there didn't exist a single Rogue deck that wasn't completely based around how busted this card was. It later became a 4 mana spell that dealt its damage only to enemy minions, a change which made the spell too impractical to use until Rogue received some stronger weapons (namely, Kingsbane).
  • Notably averted with Master of Disguise, a 4 mana 4/4 Rogue minion that gave permanent Stealth to a friendly minion, which was never actually played. Due to design space reasons and some wacky, out of nowhere gameplay moments caused by randomness (ever give a Mal'Ganis perma-Stealth? It's pretty awesome), her Stealth giving effect was limited to only last until the start of the turn.
  • Leper Gnome was a 2/1 minion for 1 mana with a Deathrattle of dealing 2 damage to the enemy hero. Unless your opponent has a Taunt minion, there is no reason for it not to just attack him/her head-on until one of their minions or they themselves take it out, either with a Hero Power, spell or a weapon. Either way, they're guaranteed to lose at least 2 health very early on. The card was eventually nerfed with the introduction of Standard, by changing its attack to 1.
  • Knife Juggler was a 2 mana 3/2 that dealt 1 damage to a random enemy whenever a friendly minion was summoned. You read that right, summoned, meaning that mass-summoned tokens like from Haunted Creeper, Muster for Battle, and Imp-losion activated this card for several extra points of damage, and with vanilla stats to boot. He was changed to a 2/2, which lowered his aggressive statline (but, to put the card in perspective, barely dented its use).
  • Arcane Golem was a 4/2 for 3 mana with Charge that gives your opponent a free mana crystal on summoning. Of course, like the aforementioned Leeroy Jenkins, this drawback means precisely nothing if you kill your opponent on the same turn you play it. Golem's main use was in a potent Warlock combo - make sure your opponent has no more than 24 HP, drop Golem, double Power Overwhelming for a 12/10, copy it with Faceless Manipulator, and attack for game. Warlock's potent card draw meant that this combo was much more consistent than it should have been, and when in doubt Golem could just be used as a 4 damage removal. Arcane Golem lost Charge when the Year of the Kraken rolled around, and gained +2 health in exchange, making it completely worthless.
  • Big Game Hunter was a 4/2 for 3 mana, a ho-hum minion that can get killed by something as simple as a 1-mana minion of spell. What made this card notorious is its Battlecry effect: it instantly kills any minion with 7 or more attack. It was designed to kill giants, but with the rise of Dr. Boom, Big Game Hunter made it in nearly every deck to counter him. This itself was not the problem- it's the fact that it was neutral, meaning that classes with crap for removal options suddenly had access to Shadow Word: Death lite, with a 4/2 attached to boot. BGH alone was responsible for helping Combo Druid and Handlock at the top of the metagame, as they effectively became decks without counters, and gave the already removal heavy Control Warrior another piece of efficient removal. It had gotten so bad that the community would shoot down any high cost legendary minion with 7+ attack, because it died to BGH. To give an idea how broken this card was, even when Big Game Hunter was severely nerfed to 5 mana, he still saw play.
  • As noted in the General section, Silence was initially underpriced. As such, Blizzard nuked two of the worst offenders - Ironbeak Owl and Keeper of the Grove. Ironbeak Owl was a neutral 2/1 for 2 that Silenced a minion. It was insanely efficient, and in basically every deck. It had its mana bumped to 3, making it significantly worse than Spellbreakernote . Keeper was a 4 mana 2/4 for Druid that either dealt two damage or Silenced a minion. Likewise, it was in every Druid deck because of its flexibility. It was changed to a 2/2, obliterating its stats-to-cost ratio.

One Night in Karazhan Nerfs

  • Call of the Wild from Whispers of the Old Gods was an 8 mana Hunter spell that summoned the three Animal Companions, Huffer, Leokk, and Misha note . The card drops an assload of stats on the board, can draw out board clears on its own without risking your other cards in hand, offers the ability to deal 5 damage to something, and protects and buffs your other minions. Call of the Wild does far too much for one card to be allowed to, and unlike many other cards on this page is not a legendary. Two Calls of the Wild back-to-back is too much for any deck to handle, not even removal heavy classes like Warrior. It was so powerful it had to be nerfed to 9 mana, delaying its effect on the game by 1 turn.
  • Rockbiter Weapon was 1 mana Shaman spell that gave a friendly character +3 attack for that turn. A completely reasonable removal card that was unfortunately given to the same class with Doomhammer, a 2/8 weapon with Windfury. 2 Rockbiter weapons plus a Doomhammer equaled half of your opponents health, and given how much burn damage Shaman has access to, it wasn't difficult to deal with the rest of it. It was nerfed to 2 mana later, making it less effective as a removal spell.
  • Tuskarr Totemic from The Grand Tournament was a 3 mana 3/2 Shaman minion that could summon any random totem. Any of them, including the overstatted Totem Golem, a card draw engine in Mana Tide Totem, and a major damage booster in Flametongue Totem. Tuskarr Totemic could effortlessly snowball games to the point he could decide games the instant he was played. As this video demonstrates, landing on a non-basic totem was such a high roll that it increased your odds of winning by as high as 30%. He was nerfed to only summon the basic hero power totems, leaving the card out in the dust.
  • Execute was a 1 mana spell that destroyed a damaged enemy minion. Probably the best removal spell ever, as Warrior had access to multiple spells that could ping minions and simply got more as time went on, particularly after Whispers of the Old Gods. The real issue, however, was that because of how cheap it is, faster Warrior decks could run it to deal with big problems without sacrificing much of anything, and simply snowball the game from there. Execute was nerfed to 2 mana; irrelevent for Control archetypes, but painful everywhere else.
  • Back in beta, there was an infamous Gorehowl+Alexstrasza OTK combo. The main card in that combo was Charge, which was originally a 1 mana spell that gave Charge to a friendly minion. The sheer power of it resulted in the card getting watered down to a 3 mana spell that also gave +2 attack. It was pretty much fine after that, up until the Worgen OTK deck emerged during the Old Gods era.note  Combined with Warrior's outstanding card draw and survivability, you had a situation not unlike Patron Warrior where they could kill you in one turn with a massive burst damage combo with little hope of stopping it. Charge got nerfed again, this time to a 1 mana spell where the chosen minion can't attack heroes, most likely killing Combo Warrior forever.
  • Abusive Sergeant, a 1 mana 2/1 that granted a minion +2 attack until the end of the turn. Sergeant was probably one of the best aggro cards ever printed, potentially allowing friendly minions to trade up with minions several points of mana more expensive than them or granting more face damage in case you need to pick up the pace, and had an aggressive statline that allows it to continue getting good trades or peck at your opponents health. Abusive Sergeant was changed to a 1/1, successfully curbing its influence.
  • Yogg-Saron, Hope's End is a 10 mana 7/5 minion from Whispers of the Old Gods that when played casts a random spell on random targets for each spell you played since the game began. Many players thought it was a joke. They were wrong. The thing about Yogg is that most spells tend to be purely beneficial, meaning that statistically he can build a large board, draw plenty of cards, deal face damage, and wipe the enemy board clean, all for the price of one card. His lack of reliability is a non-issue when using him a last resort - after all, he can't really screw you if you're already in a losing situation. He was, essentially, a much wackier version of the often hypothesized "50% chance to win the game" card. After his infamous antics in several tournaments during 2016, as well as his banning from Firebat's fan-tournament, Blizzard had had enough and changed him so that if he is either silenced or removed from the board in any way, the spell spree stops.

Mean Streets of Gadgetzan Nerfs

  • Spirit Claws, from One Night in Karazhan, was originally a 1 mana 1/3 Shaman weapon that gained +2 attack while you controlled a minion with Spell Damage. It was indisputably the best weapon ever printed, beating out even Fiery War Axe, a deliberately overpowered weapon. Obtaining the +2 attack is fairly easy for Shaman, as their hero power has a chance to roll a Wrath of Air Totem that has innate spell damage, as well as Bloodmage Thalnos and Azure Drakes to get the damage on demand. Spirit Claws, when swung three times with the buff active, is effectively a 1 mana Pyroblast when aimed at the face and offers psychotic tempo when used on minions, and could be equipped from the very start of the game. Spirit Claws had its cost bumped up to 2, meaning that it can no longer be equipped on turn 1 when going first and requiring the coin when going second. More importantly, it slowed down its ability to combo with the 1 in 4 hero power, reducing its overall reliably by a massive margin.
  • Small-Time Buccaneer from Mean Streets of Gadgetzan was a 1 mana 1/2 Pirate that gained +2 attack while his owner had a weapon equipped. It almost seemed balanced, right up until you notice that the three classes with cheap, potent weapons (Shaman, Rogue, and Warrior) were also pretty gross aggro classes. With that in mind, Small-Time became a Flame Imp without a downside that also activated Pirate synergies, and could threaten loads of face damage just for the price of 1 mana, especially in conjunction with Patches the Pirate (see below). Small-Time eventually received a cutting nerf that reduced his health to 1, making him significantly less potent and more easily answered going second.

Journey to Un'Goro Nerfs

  • The worst completed quest to have been on the business end of had to be The Caverns Below, a Rogue quest where you had to play 4 minions of the same name. With minions like the Brewmasters which can put back other minions, and spells like Shadowstep and Mimic Pod, a crafty/lucky Rogue could complete this quest before their fifth turn! And the reward for completion? Crystal Core, a 5 mana spell which sets all of your remaining minions' stats (deck, hand, and on the board) to 5/5! What makes it particularly nasty is that 1-mana Charge minions such as Southsea Deckhand, Patches, and freaking Stonetusk Boar keep the stat boosts, which can set up OTK combos with the remaining bounce effects. Worse, Crystal Core can be played for a measly 2 mana thanks to Preparation. This deck archetype was so powerful and popular that it forced every single deck to tech in counters to it in order to be viable. A deserved nerf bumped up the quest requirement from 4 to 5, making it harder to blow out your opponents.
    • ...Only it wasn't quite enough for the card. (See The Witchwood nerfs)

Knights of the Frozen Throne Nerfs

  • Innervate, a 0 mana Druid spell that formerly gave the owner 2 mana crystals for that turn only. This card could do some insane stuff very early, such as: a turn 8 Ultimate Infestation, a turn 7 Ysera, 5 mana worth of tokens ready to be buffed, and an extra set of mana to use for combos when already at ten mana (such as Malygos shenanigans). Even in the vanilla game, a turn 1 Chillwind Yeti was enough to make anybody concede on the spot. Innervate was singlehandedly responsible for making sure Druid stayed in the meta-game, dodging nerf after nerf, until Knights of the Frozen Throne finally knocked it down to size by reducing the amount of mana it gave to 1, making it on par with the Rogue card Counterfeit Coin.
  • Spreading Plague, from Knights of the Frozen Throne, was a 5 mana Druid spell that summoned a 1/5 minion with Taunt, and summoned more of them until you possessed as many minions as your opponent. It's comparable to Frost Nova in that it stalls the game until you can get your bigger, better plays, which is a big deal for a class with poor early-game. Additionally, the 1/5 tokens can be buffed by Mark of the Lotus and similar cards to build a massive board from just a few resources, while protecting higher priority targets like Fandral Staghelm and Vicious Fledgling. Even without any synergy cards, Spreading Plague on its own stops aggro in its tracks, and if they have 7 minions on the board, it may as well be a death sentence. Spreading Plague was announced to receive a nerf to 6 mana roughly 3 weeks after Knights was launched, making it the fastest recorded nerf in the entire game. For the record, even at 6 mana, it remains on many players' most hated list.
  • Hex was a 3 mana Shaman spell that transformed a minion into a 0/1 Frog with Taunt. There's no reason to make this more complicated than it is; this was the best removal option in the entire game by a country mile, and most Shaman match-ups involved the Shaman's opponent playing around it as best they could while trying to take them out. Hex was changed to 4 mana, making it in line with the Mage's Polymorph, which possesses a similar effect.
  • Fiery War Axe, originally a 2 mana 3/2 Warrior weapon, was often considered one of the most powerful Warrior cards ever printed due to its sheer power and cheap cost that would allow the Warrior to kill off almost every 2 drop the opponent played while still retaining a 3/1 weapon ready to swing again. No viable Warrior decks ever went without this weapon and the win rate of a Warrior increased by at least 50% if the player draws this card in their opening hand. War Axe eventually got the axe and was changed to a 3 mana weapon, turning it from one of the strongest weapons in the game into one of the worst.
  • Murloc Warleader, a 3 mana 3/3 Murloc that originally gave friendly Murlocs +2/+1, stood strong as the key enabler of Murloc decks, due to granting massive stat bonuses for little mana, but because Murlocs kind of, well, sucked, he never thrived up until League of Explorers and Journey to Un'Goro. League introduced Anyfin Can Happen, a spell that allowed Murlocs to be usable as an OTK package, while Un'Goro brought forth Gentle Megasaur, Rockpool Hunter, and Sunkeeper Tarim (see Un'Goro below for his entry), a set of minions that allowed Murlocs to stay on the board, ready for those juicy buffs. Warleader's influence was enough that Knights of the Frozen Throne removed the health bonus from his effect, ostensibly to make the effect "less confusing", but also making large Murloc boards much less sturdy.

Kobolds and Catacombs Nerfs

  • Raza the Chained is the Priest Legendary from Mean Streets of Gadgetzan. His Battlecry permanently changed your Hero Power to cost 0 if your deck had no duplicates. While not that impressive by himself, he essentially rewrote the meta with the inclusion of Shadowreaper Anduin. As detailed in Shadowreaper's entry in Knights of the Frozen Throne, the combination of cards allowed for extremely easy one-turn kills. He was changed to only reduce the cost to 1, limiting the damage output. Notably, he is the only Priest card that was changed post-release.
  • Patches the Pirate. He was a humble 1 mana 1/1 Pirate with Charge by nature, but after you play any pirate, he blasts himself out of your deck onto the battlefield ready to fight. What should be a simple effect to give Pirate decks a small boost ended up being one of the strongest Aggro cards ever, and a mandatory card for any deck that even casually ran Pirates. He's a reverse Mad Scientist in that he gives all of your pirates a one-time Battlecry of "Draw and summon a Stonetusk Boar". When used with N'Zoth's First Mate, you essentially get a cheaper Muster for Battle, an already undercosted card, with one less 1/1. Even just getting him off of Swashburglar or Southsea Deckhand is already better than Alleycat. While a meager 1/1 doesn't seem like much, it's a 1/1 that you got for free, meaning free face damage, a free ping, a free activator for Bloodsail Cultist, or a free target for buffs like Cold Blood. Even classes that didn't have any Pirate synergies ran Bloodsail Corsair and South Sea Captain just for Patches' effect. He was that good. In the nerfs, he lost Charge, removing his instant damage.
    • Patches was even more broken in game modes where you can field multiple of him in a single deck. Such is the case in the All Star Tavern Brawl, where a player may have 22 copies of him in the deck, resulting in a constant stream of 7 damage to the face from the very first turn. It's also possible to collect multiples of him in a Dungeon Run as Warrior or Rogue for an incredible aggressive start.
  • Bonemare was a 7 mana 5/5 neutral minion that gave a friendly minion +4/+4 and Taunt. Simply put, it provided an assload of tempo, essentially being a 3 mana 5/5 with an improved Blessing of Kings taped onto it. Aside from certain Combo and minion-light Control, there is no deck that couldn't benefit from this effect. It's partially immune to most direct removal, provides Taunt to stop aggro decks, more damage for tempo or aggro, better stats for trading, and two big threats for Druid to ramp into. The only weakness the card has is depending on another minion being on the board, something that's not all that challenging. Most of all, it's Common, meaning anyone can get them for dirt cheap and it's also readily available to create great board swings in Arena. It was nerfed to 8 mana, slowing down how fast it comes out while also making the stats more in-line the cost.
  • Corridor Creeper was a 7 mana 5/5 neutral minion that got cheaper for every minion that died while it was in your hand. During previews, many reviewers didn't rate it very highly, until they suddenly realized that it gets discounted for every dying minion, friendly or enemy. Just playing the game normally and making three even trades discounts it to a 1 mana 5/5. By January 2018, Corridor Creeper became insanely popular — aggro decks use it as a cheap giant body when they inevitably have their minions beaten back or to recover from a boardwipe, and control decks use it as a follow-up to a big boardwipe. It's also a Beast to boot, opening up easy Beast synergies using a 0-cost Creeper. It was nerfed to a 2/5, greatly reducing how swing-y the minion is; this resulted in Corridor Creeper being removed from just about every deck other than Evolve Shaman, though it found new life in Odd Paladin after the rotation.

The Witchwood Nerfs

  • Call to Arms, from Kobolds and Catacombs, was a 4 mana Paladin spell that Recruited 3 minions that cost 2 or less. No beating around the bush - Call to Arms was easily the most insane board flooding card in the entire game. Not only did it summon three minions, those minions can include some incredibly high-value stuff like Righteous Protector, Knife Juggler, and Dire Wolf Alpha. Not only that, but it also thinned your deck out by three, reducing the chance to draw lower-cost cards later in the game (not unlike another infamous Paladin game-breaker). It also fit spectacularly into Even Paladin, where deckbuilding restrictions ensure that you'd always get three 2-drops. The card was nerfed to 5 mana, which worked in three aspects: It becomes unusable in Even Paladin, it's irrelevant in Odd Paladin (nobody wants three 1-drops for 5 mana), and it's efficiency is much more reasonable for any other Paladin deck.
  • The Caverns Below makes its return! While the initial nerf to the card was sufficient in reducing Quest Rogue's power level, the rotation of numerous aggro cards and the additions of Sonya Shadowdancer and Vicious Scalehide revitalized the deck - and it was about as frustrating as it was last time. It still stomped Control, and still got rolled by Aggro. As such, Crystal Core had it's potency reduced - it makes your minions 4/4s instead of 5/5s.
  • Dark Pact, from Kobolds and Catacombs, was a 1 mana Warlock spell that destroyed a friendly minion and restored 8 health to your hero. Warlocks hit the jackpot with this card - it provided monstrous healing, which is otherwise scarce for the class, and it allowed you to blow up your own minions on demand, which is fantastic when used for Carnivorous Cube shenanigans and nuking Possessed Lackey. Pact had its healing cut down to 4, making it in line with the similar Sacrificial Pact but not hurting the utility.
  • Possessed Lackey, from Kobolds and Catacombs, was a 5 mana 2/2 that, on death, Recruited a Demon. Unlike Skull of the Man'ari, which is similar but possesses clear counterplay, Lackey could be killed the second it hits the board to pull powerful stuff early like Voidlord, which stops aggro dead still, and Doomguard, which can be duped for a series of powerful Chargers to end the game fast. Lackey had his mana cost increased to 6 to hopefully curb his power.
  • Naga Sea Witch, from League of Explorers, was a 5 mana 5/5 with the effect of changing the cost of all cards in your hand to 5, became a Game Breaker in Wild after a buff allowed her effect to apply before any discount effects. This means that the Giants, which are so expensive one needs to build a deck around them to use, can now cost 0 with Naga Sea Witch on the board with only very minimal condition requirement, allowing for a field full of 8/8s as early as turn 5. In response, Sea Witch was changed to 8 mana, to give players more time to prepare for the parade of Giants.
  • Spiteful Summoner, from Kobolds and Catacombs, was a 6 mana 4/4 that revealed a spell from your deck and summoned a random minion with cost equal to the spell's. While it sounds like an extremely variance-based card, players got around her effect by building Tempo decks containing all minions except for a few high-cost spells. This was most successful for Druid, which used the already gamebreaking Ultimate Infestation (see Knights of the Frozen Throne). While it was still high variance with lots of low rolls on release, that changed for the Year of the Raven. The rotation got rid of high rolls Y'Shaarj and Deathwing, Dragonlord, but also got rid of every single notable low roll. The worst card to pull now was Emeriss/Sea Giant, an 8/8. Past that, you have the 7/14 Ultrasaur, the 12/12 Deathwing, or the granddaddy, the 12/12 can't be targeted by spells Tyrantus. Cheating out a card that big as early as turn 5 was a total nightmare for your opponent. Spiteful had her mana cost increased to 7, giving the opponent more time to draw an answer.

The Boomsday Project Nerfs

  • A game-breaking combo was avoided before this set even launched. Shadowboxer was an unassuming Priest Mech from the Goblins vs Gnomes set that dealt 1 damage to a random enemy after a character was healed. It didn't see much play, but came to attention in Kobolds & Catacombs after an interaction with Unidentified Elixir potentially granted the Shadowboxer Lifesteal, creating a loop where its ability caused healing and thus triggered itself, eventually dealing as much damage as your Hero was missing health. In general, this was gimmicky and unreliable due to the Elixir only having a 1 in 4 chance of giving Lifesteal. However, The Boomsday Project introduced Zilliax, a neutral Legendary that could give any Mech Lifesteal. People quickly figured out a fast, reliable OTK deck even before the expansion launched, so Blizzard issued an emergency nerf to Shadowboxer, causing its effect to only trigger from minions.
  • Aviana was a 9 mana 5/5 Druid Legendary from The Grand Tournament that made all your minions cost 1. While it began life as a meme-tastic Awesome, but Impractical card, it found a niche when Kun the Forgotten King was printed. With Kun's mana refresh, Aviana let the player unleash insane combos with cards like C'thun, King Togwaggle, Malygos, and so on. These decks were popular in Wild but still fairly inconsistent. This changed when Juicy Psychmelon (mentioned in The Boomsday Project) was printed. With the melon, Druid could draw and play all of its combo so reliably, Druid became the only real deck in the format. To cut down on combos and reduce how reliably Kun + Aviana could be drawn, she was nerfed to 10 mana.
    • The actual effectiveness of this nerf is... debatable. In most cases, it slows the combo down by one turn and forces them to run Innervate as well. Otherwise, any other Aviana OTKs play exactly the same. The combo is so broken, requiring two 10 cost cards did nothing to weaken it.
  • Mana Wyrm was a 1 mana 1/3 Mage minion that gained +1 Attack each time you cast a spell. It was one of the most powerful one drops in the game, being quite sticky and quickly ramping its damage up. It was a crutch card for any aggro or tempo mage, nearly doubling their winrate so long as it was in their opening hand. Mana Wyrm combined perfectly with those decks, since they spam low mana damage spells, letting the wyrm snowball out of control. It was changed to two mana, greatly slowing the card down and giving it a lot of new competition in the 2 slot.
  • Giggling Inventor was a 5 mana 2/1 that summoned two Annoy-o-trons, 1/2 Divine Shield and Taunt minions. It was easily one of the most stat-efficient cards ever printed, creating a 3 body spread with two separate instances of Divine Shield to get through. It was seen in numerous decks: the three sticky bodies made it ideal for decks looking to go wide and spam buffs, the efficient taunts made it desirable for any Control or Combo deck, and the Annoy-o-trons being stubborn Mechs made them prime candidates for Magnetic buffs. For the cherry on top, it was Odd, giving it free reign in Odd Rogue. It was so unanimous, people began running Blood Knight just to counter the thing. Despite The Boomsday Project not having many popular cards, Giggling Inventor singlehandedly forced the meta to be dominated by Zoolock, Deathrattle Hunter, and Odd Rogue. It was brutally gutted to 7 mana in response, seriously limiting its viability.note 

Rastakhan's Rumble Nerfs

  • Druidstone had been in full swing for nearly two years, and showed no signs of slowing down. The culprits? Wild Growth and Nourish. The combination of those two cards let Druid ramp their mana much faster than other classes, executing combos with Hadronox, Aviana, Malygos, and others, or just powering out big cards like Ultimate Infestation and Spreading Plague before other classes could react. In order to solve this and hopefully prevent this going forward, the ramp cards had their cost bumped by one mana each.
  • Level Up! was a fairly unassuming buff from Kobolds & Catacombs that gave your Silver Hand Recruits +2/+2 and Taunt for 5 mana. Originally hard to get value from, that changed when Baku entered the picture, creating Odd Paladin. With Odd Paladin's hero power creating two Recruits each turn, Level Up! always found a strong board at some point, creating a wall to protect high-value minion and the face, providing a huge source of damage on the opponent, or both. It was brutally axed to 6 mana, where it compares horribly to Sunkeeper Tarim, and prevents its use in Odd Paladin forever.
  • Leeching Poison, originally a 2 mana spell that gave your weapon Lifesteal. Pretty bad on its own, it was completely busted with Kingsbane, which turned the weapon into an infinite and massive source of healing. In order to nullify its effect without changing how it's used with most other weapons, it was changed to a 1 mana spell that gave Lifesteal for a single turn only.
  • Saronite Chain Gang, a 4 mana 2/3 Taunt that summoned an exact copy of itself. It was notorious as an overstatted Taunt that got better as it received in-hand buffs. However, its greatest feat was the broken combination with Shudderwock (see Year of the Raven below), which let the Shaman have infinite 1-mana Shudderwocks to play. Blizzard gave Shudderwock the boot and lowered Chain Gang's effectiveness by having it summon another 2/3 Saronite Chain Gang instead of a copy of itself.
  • The Spellstone cards are designed with Magikarp Power in mind. They start out mediocre or weak for their cost, but become stronger by being upgraded through an action specified on their card. That is, except for the original Lesser Emerald Spellstone, which started out decently strong and just got stronger. 5 mana for 6/6 spread across two bodies is alright to begin with, but when fully upgraded, it goes up to a massive 12/12 across four. It's also trivially easy to upgrade, as all you need to do is play two Secrets with the card in hand - and Hunter has some pretty good Secrets to begin with, generating ludicrous amounts of tempo in tandem with the Spellstone's tokens. A fully upgraded Emerald Spellstone usually spells doom for any opponent that doesn't happen to have some form of area removal ready, as it's otherwise nearly impossible to deal with efficiently. Because of this, it was bumped to 6 mana to put it more in line with other Spellstones and its own effect, while making it impossible to combo with Tundra Rhino (unless you go second and hold onto The Coin for the whole game).
  • Hunter's Mark, once a simple 0-mana Hunter spell that reduced a single minion's health to 1, was easily the best removal spell in the game. With the trivial requirement of a single damage, Hunter could flexibly remove any minion it wanted to. Originally this was balanced by the class being a heavy aggro base, but as Hunter received more and more solid Midrange and Control cards, Hunter's Mark slowly got out of hand. It was cautiously nerfed to 1 mana during Whispers of the Old Gods even before it could become broken, but still became a breakout card, especially after the release of Candleshot. Since it was far too efficient, it was bumped again to 2 mana.
  • If Hunter's Mark was the king of combo'd single-target removal, Equality was the god it worshipped. Originally 2 mana, the spell reduces the health of all minions to 1. This works exceptionally well with the Paladin hero power, using a bunch of 1/1s to trade with your opponent's shrunken board. Where it got really nasty however was when combined with Consecration or Wild Pyromancer, clearing any amount of health for just six or four mana respectively. No Control, Combo or Midrange Paladin would be caught dead without the card. It was doubled to 4 mana, slowing down how fast the pair came out (although if Shrink Ray had proven anything, not reducing its playability by that much).
  • Flametongue Totem was a 2 mana 0/3 Totem that gave adjacent minions +2 Attack. It was a very powerful aggro card that made efficient trades a breeze. What really brought Flametongue into the spotlight, however, was Even Shaman, whose discounted hero power meant that they were never short of tokens to buff with Flametongue, and could also use the buff as a finisher in conjunction with things like Al'Akir the Windlord or a Sea Giant given Windfury. Because of its ubiquitous play in any even slightly aggressive Shaman, it was bumped to 3 mana, which also makes it unplayable in Even Shaman.
  • Cold Blood is a dreaded finisher for Aggro Rogue, providing +4 Attack on any minion for 1 mana as long as it was Combo'd. While not that strong compared to Paladin's Blessing of Might, it became truly problematic with Baku the Mooneater, as detailed below. Odd Rogue's high damage output, snowball potential, and sticky board meant finding a target was simple, and the buff was often the killing blow. Cold Blood was raised to 2 mana, barring it from Odd Rogue.

Rise of Shadows Nerfs

  • Preparation, a Classic 0-mana Rogue spell that reduced the cost of your next spell that turn by 3. Prep was the biggest mana cheat in the entire game, cutting the cost of any card by an absurd amount. On top of that, it has massive synergy with Rogues, working with Combos, Edwin VanCleef, and the multitude of inexpensive cards that their disposal. Prep was so strong, Blizzard was afraid to print powerful Rogue spells, meaning that pretty much no non-Classic Rogue spells outside of Raiding Party ever saw serious play. Because of this, it was nerfed to only reduce the cost by 2.
  • Raiding Party, from Rastakhan's Rumble, was a card meant to support the Pirate Rogue archetype, and while it's a good card in that deck, it had much more significance in other Rogue decks. This card elevated Kingsbane Rogue from a fringe archetype to a solid high tier deck for its weapon drawing effect (where the only other guaranteed way to draw it was from Cavern Shinyfinder), which also had the convenience of drawing Cutthroat Buccaneers to buff it. Where this card really went out of control was when Waggle Pick was added in Rise of Shadows. A 4-mana 4/2 weapon is not only an extremely solid baseline, but it also just happens to have the exact amount of Attack required to summon 0-mana Dread Corsairs. Being able to summon 6/6 worth of bodies with Taunt with a weapon from a single card was one of the main driving factors in Tempo Rogue becoming an oppressive force in the Year of the Dragon meta. To deal with this, Raiding Party was bumped to 4 mana.
  • EVIL Miscreant seems innocent enough on paper; a 1/5 at 3 mana isn't very impressive, plus requiring a Combo to generate some 1/1 Lackeys isn't all that, is it? You'd be wrong. Turns out Lackeys are very useful for their variety of effects, from card generation, removal, or board value, and in the case of Witchy Lackey, likely negating the Miscreants poor stats. Not only that, Lackeys make for great Combo activators, compared to most other token generators in the past being held back by being too weak or requiring too much of a tempo sacrifice to generate. The Lackeys only helped empower the Rogue's already good Classic card set, and so EVIL Miscreant was the other key card that elevated Tempo Rogue to the top of the meta. It was nerfed to a 1/4, weakening the card, although not by much.
  • Archivist Elysiana was an 8 mana 7/7 with the very unique effect of Discovering 5 cards and replacing your deck with 2 copies of each. That sounds memey, but there's absolutely nothing preventing you from waiting until your deck is empty, then playing her to shuffle in 10 cards and massively delaying fatigue. But the really, really insane thing was combining it with Youthful Brewmaster or Baleful Banker, giving yourself a 50 to 60 card deck. Naturally, when your opponent is playing a 60 card deck, you want to as well. This meant a disproportionate number of Control mirrors were decided not by the players, but ended in draws because of the turn limit. In response, Elysiana was increased to 9 mana, requiring you to save a Coin to cheat her out.
  • Again, an unassuming Priest card was preemptively changed to prevent a game-breaking combo. Reckless Experimenter was a ho-hum minion, originally known as the combo-enabler for Mecha'thun Priest but not really making an impact elsewhere. But with the incoming addition of SN1P-SN4P in the Rise of the Mech event, people realised that her effect let the Priest have infinite damage as early as turn 5 so long as they had a single Mech in play (something easy to do with Coppertail Imposter). Reckless Experimenter was issued an emergency nerf that made her effect unable to reduce the cost below 1.

    Hall of Fame 
Starting in 2017, the devs began rotating problematic cards from the Classic set into the Hall of Fame, a special set only available in the Wild Format. This is done whenever a card is well-liked or at least interesting, so the team doesn't want to nerf it, but causes design problems or hurts deck variety.

Year of the Kraken

  • Old Murk-Eye is a 4 mana 2/4 Murloc with Charge that gains +1 attack for every friendly Murloc. It was mostly just a neat finisher for Murloc decks right up until League of Explorers brought Anyfin Can Happen into the game, a 10 mana Paladin spell that summons up to 7 friendly Murlocs that died that game. Murk-Eye offered two major things to the resultant Anyfin Paladin deck: a decent midgame minion that can remove some weeny minions and a devastating combo piece that can finish the job when working together with Bluegill Warriors and Murloc Warleaders. For dramatically increasing the consistency of an already consistent deck, Murk-Eye was completely banned from Standard and for Team 5 to save face they took the rest of the Reward set (which were all pretty much unplayable) with him. The Reward set was then added to the Hall of Fame when it was established proper.

Year of the Mammoth

  • Ice Lance is a 1 mana Mage spell that freezes a target or, if they were already frozen, deals 4 damage to them. Ice Lance is famous for being a core piece of the Freeze Mage OTK, due to its monstrous power to cost ratio, and notably becomes free when combined with Emperor Thaurissan. Team 5 took multiple steps to hit Freeze Mage throughout the years to reduce its effectiveness, and in the end barred Ice Lance from Standard to make sure it stays down this time.
  • Conceal, a 1 mana Rogue spell that gives all friendly minions Stealth until the start of the turn. Infamously used in conjunction with Gadgetzan Auctioneer, mostly guaranteeing that the merchant stays on the board outside of a Flamestrike or Twisting Nether, allowing the Rogue to cycle through their deck next turn. It's wasn't just Auctioneer though; Conceal could also protect dangerous minions like Edwin VanCleef, Questing Adventurer, or Red Mana Wyrm to prepare to wreck house next turn, and was subsequently shown the door from Standard.
  • Power Overwhelming is a 1 mana Warlock spell that gives a friendly minion +4/+4, but also dies horribly at the end of the turn. What started out written off as a goofy risk-and-reward card turned out to be a devastating combo card when used together with way too many cards to count. It's most famous use is the OTK combo with Faceless Manipulator; use two Power Overwhelmings on a Charge minion, copy it with Faceless, and attack for game. After all, dying at the end of the turn only matters if the turn ends. But that's just one of the card's many uses, there's also: using it with Sergeant Sally for a makeshift Shadowflame, use it with the actual Shadowflame, buff a minion to terrifying levels then steal or copy its stats with Void Terror or Faceless Shambler, or simply give it to a humble Imp to kill a 5-cost minion. Power Overwhelming was too flexible for its own good, and was banned from Standard.
  • Azure Drake is a 5 mana 4/4 Dragon with Spell Damage +1 and draws a card upon summoning. It's a perennial favorite for game design enthusiasts among the fanbase due its simplicity, power, and inability to make someone rage, but a major issue many overlook is its versatility. Azure Drake essentially won the lottery with its effect variety: it's a Dragon, meaning it's good in Dragon decks by default, it has barely enough attack to be threatening (while dodging both of Priest's Shadow Word removal spells) and enough health to dodge a handful of removal, the extra spell damage is deceptively valuable, is uncontested in its mana slot, and it has one of the most undercosted card draw effects in the game. The Drake is well liked for the most part, but to assure long-term health for the game, it was booted out of Standard in 2017.
  • Sylvanas Windrunner is a 6 mana 5/5 who takes control of a random enemy minion on death. By a mile, the single best Deathrattle minion in the whole game; there's almost nothing that can beat Sylvanas in a fight and survive except for minions who summon other minions to be stolen like Onyxia or Dr. Boom. Even scarier, she simply got better over time with the addition of Deathrattle synergy cards like Unearthed Raptor and N'Zoth. To open more design space for Deathrattle synergy and overall more variety in the 6-cost slot, Sylvanas was kicked out of Standard with the Year of the Mammoth.
    • Notably, she was even better in the beta, where she costed 5 mana instead. A Warrior who uses Sylvanas in conjunction with Brawl would destroy all enemy minions and leave one for himself.
  • Ragnaros the Firelord is an 8 mana 8/8 who can't attack, but deals 8 damage to a random target at the end of his owner's turn. He's the most iconic card in the game, stemming from his improbably high use-rate for such an expensive minion. Big minions in Hearthstone are typically weak due to the power of hard removal, meaning they either need to do something before getting removed or be annoying to remove in the first place. Ragnaros is the first requirement personified; he almost always either destroys something upon coming down or knocks off a quarter of the opponent's health, and if he sticks around he remains devastating because he never takes any damage from combat because technically he never attacks anything. Additionally, the RNG factor of Ragnaros can indirectly work in his user's favor, because a lucky coin flip can cause your opponent to get frustrated and start making mistakes. Eventually, Rag's power got him removed from Standard come the Year of the Mammoth, simply for outclassing all other lategame drops.

Year of the Raven

  • Ice Block, a Mage Secret from the Classic set that activated when you took fatal damage, preventing it and making you Immune for the rest of the turn. The card was a 100% two-of stalling tool for Control and Combo mage decks, letting you guarantee breathing room for at least two turns (or more if you generated them from other cards). It was exceptionally frustrating to play against, since there were limited ways to actually prevent the Secret from triggering, giving you absolutely no way to put the opponent on the clock. It was especially bad given Mage's high burst damage, since you had no way to stop it if they could lethal you after the block was procc'd. It was rotated to the Hall of Fame to encourage more deck variety.
  • Coldlight Oracle is a 3 mana 2/2 Murloc that draws two cards for each player. Sounds reasonable, since it's a weak body and comes with a severe downside to balance the upside. The problem is that the player chooses when his opponent draws two cards. Coldlight Oracle's main use was combining it with bounce effects to use its Battlecry multiple times, causing your opponent discard lots of cards and/or go far into fatigue while refueling yourself. On top of that, it being a Neutral card made "return to hand" effects hard to print. They moved it out of Standard to curb the power of fatigue decks.
  • Molten Giant is a 20 mana 8/8 that has its cost reduced by 1 for every point of health your hero was missing. Created to help give control decks major comeback turns for when they were low on life, it ended up work a little too well in Warlock, who could reliably lower his health with his hero power and get free Molten Giants, letting them either use Sunfury Protector to give the Giants taunt, or Shadowflame to wipe the enemy board. Molten Giant was eventually nerfed to 25 mana, where it became almost unplayable. However, once the Year of the Raven began, it was returned to 20 mana and instead moved to the Hall of Fame, but not before spending a couple more days in Standard with the reverted cost as a last blaze of glory.

Year of the Dragon

  • Baku the Mooneater and Genn Greymane from The Witchwood, easily the most format-warping cards this side of Patches the Pirate. While not every class could build a good Odd/Even deck, the ones that could built a great one. Decks like Odd Rogue, Even Shaman, Even Warlock, Odd and Even Paladin all became grossly efficient if not outright game-breakers. The problem was conceptual - making the Hero Power more reliable makes for very boring, predictable gameplay. You use the hero power every turn you can. It always does the same thing, so every game follows pretty much the same flow. The cards' restrictions also made every deck even more samey, since you only had half the card pool to work with, making the best cards for each slot more obvious. Given the inherit design issues with the cards, Blizzard decided to send them to the Hall of Fame a year early, taking their synergy cards with them (including the bad ones).
  • Naturalize is a 1 mana Druid spell that destroys a minion and draws two cards for your opponent. Traditionally, Druid struggles with large single-target removal. This card blows that out of the water, zapping any minion you want for just 1 mana. While it has a pretty major downside, it was more often that not weaponized, overdrawing your opponent or sending them into fatigue (particularly after a Togwaggle combo). To preserve class identity, Naturalize was rotated to the Hall of Fame.
  • Doomguard, a monstrous Warlock 5/7 Charge for 5 that discards two cards from your hand. Like all discarders, the effect can be ignored completely if your hand is empty when the Doomguard is summoned, and like all Chargers, its downside is nothing if it's used to end the game. This was traditionally a strength of Zoolock, which would play every card from their hand and own the board until Doomguard could guarantee victory. It got really broken however with anything that could cheat more Doomguards out, such as Skull of the Man'ari, aforementioned gamebreaker Possessed Lackey, or Voidcaller. Duplicating Doomguards with Carnivorous Cube or Faceless Manipulator let the Warlock deal gross face damage at no cost. It was too powerful and was barred from Standard in 2019.
  • Divine Favor is a 3 mana Paladin spell that draws cards until you have as many as your opponent. This card was essentially the backbone that Secret Paladin and Odd Paladin were supported on. Against a Control deck, an Aggro deck could near-instantly refuel after dumping their hand, making a board clear far less punishing. Drawing up to 10 cards for 3 mana is absurd. Even drawing more than two is way above the mana grade. Control Decks often had to play awkwardly and inefficiently to use up more cards than they'd like, just to weaken this one. Given how strong Aggro Paladin decks have been, Divine Favor was finally removed in the Year of the Dragon.

    Basic and Classic 
Basic and Classic cards have suffered a lot of Power Creep over the years, but their eternal status in Standard and the ever-rising number of synergies continue to expose a lot of the odd balance choices these cards had. The majority of all nerfed cards and Hall of Fame belong to this set.
  • Savannah Highmane, a 6/5 Hunter minion for 6 mana that spawns 2 2/2 Hyenas when it dies. Because of how sticky it is, a hunter can just reliably go for the enemy hero's face instead of trading, and the nasty body ensures that their opponent will need to deal with it. Combined with the hunter's naturally high amount of direct damage cards, and you have a minion that can ensure victory just by hitting the enemy hero once. And let's not get started on what happens when the Hunter gets a Tundra Rhino to stick around...
  • Flamestrike, a 7 mana Mage spell that deals 4 damage to all enemy minions. It's one of the Basic cards, so everyone has one. Yet it is the single most feared Board Clear in a Mage's arsenal, and it is not an exaggeration to say that an entire match can, and has been turned around simply from a single cast of this spell. The typical advice for playing against Mage when the game goes late is to make your board good enough to bait out their first Flamestrike (That you must always assume they have by Turn 7) but without using your really good cards.
  • Tirion Fordring is an 8 mana 6/6 Paladin minion with Divine Shield and Taunt, itself already a solid deal, and equips his owner with a 5/3 Ashbringer when he dies. Tirion's base body alone is worth paying the mana cost for, capable of trading 2 for one with mid-sized creatures, but the Deathrattle is where he truly shines. A 5/3 weapon can deal half of the enemy hero's life on its own or destroy up to 3 more moderately-costed minions, giving its user time to develop their own board and seal the game. Tirion is widely considered the king of lategame matchups and is fully capable of ending games by himself. That said, all of this was completely intentional. Paladin, as a class, was meticulously crafted with this one showstopper in mind, and as a result has a hard time winning games without him. It's only when Paladin had access to other stupid powerful cards (Muster for Battle, Mysterious Challenger) that made up for Paladin's other weaknesses that Tirion became a problem, because he went from a reward for reaching the endgame to another broken card that could make the enemy cry.
  • Two Divine Spirits used on a decently sized minion will give that minion a very high health pool, and casting Inner Fire on it gives the opponent a problem that hits as hard as it can take. Husky Starcraft and his friend Sinvicta discovered that, if you use Lorewalker Cho note  and can get your opponent to co-operate with you, you can very easily get a Minion up above 1 billion health. However, as the game moved on, the strategy became considered too gimmicky to be viable due to the amount of setup required to pull it off.
    • However, this strategy came back in Journey to Un'Goro with a vengeance with the addition of more Silence, cheap high health minions and especially cards like Radiant Elemental and Shadow Visions, and actually took the meta by storm for a while in Kobolds & Catacombs thanks to Duskbreaker keeping weeny decks in check.
  • Faceless Manipulator, the heart of more combo decks than any other card. It's a 5 mana 3/3 that becomes an exact copy of any other minion on the battlefield. Faceless is obviously insane with any big buffs and Charge minions, and has been the indirect cause for a multitude of nerfs over the years. The thing that really makes it strong however is its versatility. It doesn't need to be used as a finisher - sometimes stealing a large minion from your opponent or doubling up on one you control is good enough (prime offenders were Sylvanas and Ragnaros, two cards that were later rotated). It can create taunt walls just as easily as Charging finishers, often serving as both within the same deck. While not in every meta, it's a powerhouse whenever the game allows it.


Curse of Naxxramas

Also see Undertaker in the Nerfed Cards section.
  • Voidcaller, a 3/4 minion for 4 mana with the deathrattle of putting a demon from your hand into the field. Not only can it replace itself the second it dies, but it can summon demons with a higher cost than itself, including Doomguard, Dread Infernal, and the almighty Mal'Ganis. Even if you don't have a demon in your hand, your opponent has no way of knowing, meaning that they have to play ridiculously safely or come up with a backup plan to deal with whatever comes out of it, or use one of their very few silences on it.
  • Zombie Chow is a 1 mana 2/3 with the Deathrattle of restoring 5 Health to the opponent's Hero. This card's incredible stat line and the lack of good 1-mana non-aggressive minions means that almost every single deck archetype except for Face Hunter will run this card because it will trade off a 2 mana minion and has a big change to survive. This card singlehandedly slowed down the meta to let control decks like Priest gain a leg against aggressive decks but its brokeness had to be felt in Arena because it was considered an auto-pick every time it showed up on screen.
  • Mad Scientist. It's a 2/2 for 2 mana, itself a merely slightly below average statline, with the obscene deathrattle of putting a random secret from your deck into the battlefield. If it merely drew a secret, it would be crazy, as it lets you tutor for important cards like Explosive Trap and Ice Block. Instead, it puts the damn thing into the field at no extra charge. Hunter secrets cost 2 while Mage secrets cost 3, meaning that this card is worth 5-6 mana (1.5 for the body, 1.5 for the specific draw, 2-3 for the secret) in value for something that can be absentmindedly dropped on turn two, ready to contest any 1-drops or 3/2s your opponents play. Out of all the cards booted from Standard once formats came around, even with several fan favorites leaving, there was universal rejoicing that Mad Scientist was finally gone.
  • Sludge Belcher, a 5 mana 3/5 Taunt minion with the Deathrattle of summoning a 1/2 Slime that also has Taunt. This card's annoying Deathrattle means that it has to be killed twice in order to completely being get rid of it and its solid body is excellent for control decks to bait out Silence. Like Zombie Chow, it was also considered an auto-pick when offered in Arena.

Goblins vs. Gnomes

Also see Shadowboxer in the Nerfed Cards section.
  • Unstable Portal, which is the leading candidate for the most hated card in Hearthstone. It's a 2 mana Mage spell that adds a random minion to the owner's hand and reduces its cost by 3. On top of it's status as a cheap spell at a time when cheap spells were invaluable for Mage, its effect is randomness gone horribly wrong; as many pro players noted, Unstable Portal's main strength is that even if it whiffs you still don't lose the game, while most other times it will end the game by itself. Even if you get a Wisp instead of Ragnaros, a Wisp is still a minion you can put on the board, while most other times you'll get something insane like a 5-cost Tirion Fordring or a 3-cost Boulderfist Ogre. Even terrible cards like War Golem aren't that bad if it gets played as a 4-mana 7/7.
  • Goblin Blastmage, a 5/4 for 4 mana Mage minion that deals 4 damage split amongst all enemies if you control a Mech. This card, combined with Mechwarper's minion spam, made it nigh-impossible for an opponent to catch up if they were behind, because Blastmage would kill any threats they put down or did enough face damage to just go for the kill. The vanilla stats, while lax nowadays, were a big deal back then because he could kill most minions and likely survive, while being sturdy enough that it survived basic removal like Frostbolt.
  • Muster for Battle is a 3 mana spell that allows the Paladin to summon 3 1/1 Silver Hand Recruits and equip a Light's Justice. This card's effect effectively allows the Paladin to summon 3 minions in one turn for 3 mana, which is quite good on its own when combined with Blessing of Kings for 4 mana, but the thing that made this card completely broken is that it also equips the Paladin with a 1/4 weapon, effectively allowing them to profit even if the opposing Hero uses a board clear. Muster was often comboed with quartermaster, giving a Paladin player 11/14 worth of stats (and a weapon) for 8 mana.
  • Shielded Minibot is a 2 mana minion that is very aggressively statted, with 2/2 and divine shield. This statline, in the best-case scenario, enables Minibot to trade with other strong early-game minions such as two Flame Imps, Totem Golem or Haunted Creeper, giving Paladins a sorely-needed way to not fall behind in the earlygame against aggro decks such as Zoolock or Face Hunter. In addition to the aforementioned Muster For Battle, the fact that Minibot was frequently played in Wild Paladin decks up to the Call to Arms nerf is a testament to its power.
  • Velen's Chosen, a 3 mana Priest spell that buffs the minion by 2/4 and gives it +1 Spell Damage. This card is considered one of the best Priest cards ever printed in the game because its cost allows the Priest to buff their early game minions to be a giant trading machine that the Priest can keep healing back. That is without talking about the Spell Damage it offered, which allows the Priest to buff their board clear to be more mana-efficient. Many players bemoan the loss of this card when Standard hit and it was still used as a measuring stick when creating Priest cards, especially spells or buffs. This card is so powerful that the community mocked Blizzard when they tried to print its Poor Man's Substitute Power Word: Tentacles, a 5 mana spell that buffs for 2/6.
  • Mechwarper, the centerpiece card of all Mech decks, is a 2/3 for 2 mana that reduces the cost of all Mechs in hand by 1 mana. Most Mechs are very efficient for the cost to start with, like the 3/4 for 3 Spider Tank and the 1/2 Taunt Divine Shield for 2 Annoy-o-Tron, and are also quite cheap, meaning that if Mechwarper survives turn 2, it's very likely the opponent will spam the board with multiple minions for nothing at all, and even to this day there is no AoE spell that would be capable of dealing with such a board outside of Doomsayer. Plus, this effect stacks; two Mechwarpers is an absolute nightmare that can create unwinnable circumstances, especially when combined with...
  • Piloted Shredder. Once the most used neutral card in the game and one of the most efficient as well. As a 4/3 for 4 mana that summons a 2-cost minion when it dies, it has just enough attack to kill almost all minions that cost the same or less than it while leaving a body behind, which can be used to finish off anything that survived the first hit. With this in mind, there is practically no other 4 mana minions worth using as there is nothing that can straight up beat Piloted Shredder, they can only trade with it at best or accomplish nothing and die at worst, with only utility minions like Water Elemental getting any free passes. Plus, it has a chance to spawn overstatted minions like Millhouse Manastorm. The only downside to using it is the possibility it might spawn Darnassus Aspirant or Doomsayer (which isn't that bad if you're losing board control), but considering how often it hits compared to how often it misses, who cares?
  • The notorious Dr. Boom. He's a 7/7 for 7 mana that summons 2 1/1 Boom Bots into battle with him, with each of them dealing 1-4 damage to a random enemy on death. Because of how many bodies he brings to the board, very few cards can completely deal with Dr. Boom by themselves, requiring inadequately used resources just to get rid of him. Adding to this, he costs 7 mana, which means he can be played after a particularly high value 6 drop, a list which includes but is not limited to the aforementioned Savannah Highmane, and the later mentioned Emperor Thaurissan and Mysterious Challenger, meaning that when he shows up the opponent likely lacks the required removal to beat him. Finally, there's his flexibility; Dr. Boom will provide nothing else of use other than astronomical value, which despite what it sounds like is incredibly good. This means that while he's not the best card in the game by any means, his sheer power and ease of use mean that there are few decks that wouldn't be improved with Dr. Boom, even a select few aggro or combo decks.

Blackrock Mountain

  • Emperor Thaurissan. He's a 5/5 for 6 with the ability to reduce the cost of all cards in his owner's hand at the end of each turn. In control decks, he's good because he can reduce the cost of the big lategame minions so that they can be played earlier and more frequently, but it's nothing too terrible until he gets put into a combo deck. Thaurissan alone singlehandedly created loads of overtly strong combo decks, most infamously Patron Warrior, while bolstering those that already existed, as the nature of his ability meant that not only could the game winning combos be done earlier but they could made even stronger. To give an idea of how much impact he had, full 30 damage one turn kills became the norm instead of a once in a blue moon sort of thing.

The Grand Tournament

Also see Tuskarr Totemic and Aviana in the Nerfed Cards section.
  • Mysterious Challenger, a 6/6 for 6 mana Paladin minion that puts up to 5 secrets from your deck into the battlefield for free. On average, he pulls Avenge, Noble Sacrifice, Repentance, Competitive Spirit, and Redemption from the deck, which means his owner will no longer have to worry about drawing any of them and giving them better odds of drawing their late game cards, like Tirion or another Challenger. On top of this, killing him is a nightmare, because the combination of secrets makes it so that if you kill him with spells, he comes back with 1 health while trying to kill him with an attack will negate the attack and give him +3/+2.

The League of Explorers

Also see Naga Sea Witch in the Nerfed Cards section.
  • Tunnel Trogg, a 1/3 for 1 mana that, whenever you play a minion with Overload, gains +1 attack per crystal overloaded. Trogg's statline makes it hard to kill early on without a good earlygame removal card like Fiery War Axe, and despite what it looks like its effect can quickly get out of control, the main reason for which is because of its companion cards Totem Golem and Feral Spirit. The former is an overstatted 2-drop with 1 Overload to compensate, which this card turns into an advantage, while the latter summons 2 2/3 Spirit Wolves with taunt that can protect the Trogg, while giving it +2 attack due to the Overload. The final straw to "broken" territory was Flamewreathed Faceless added in Whispers of the Old Gods, a gigantic minion for a piddly 4 mana that demands a completely different answer from Trogg - meaning that if you chose to mulligan so you can kill Trogg, you get smacked down by Flamewreathed, and vice versa.
  • Reno Jackson, a 6 mana 4/6 that will fully restore your hero's life as long as you don't have any duplicate cards, will break the will of any player going up against his specialized deck. Basically you let the opponent waste cards and life going against your random minions and just when they think they have you, usually when your life is less than ten, you throw out Reno and watch your opponent despair at the thought of grinding you down again with a lot less cards. For maximum despair play a Brewmaster or another card that allows you to put Reno back in your hand, its enough to make your opponent quit. Of course this is assuming all goes well and depends a lot on drawing a good curve, as well as not letting your opponent have any good cards by the time you play Reno.

    Year of the Kraken 

Whispers of the Old Gods

Also see Yogg-Saron, Hope's End and Call of the Wild in the Nerfed Cards section.
  • Fandral Staghelm is a 4 mana 3/5 Druid minion who combines the effects of your Choose One cards. When played early on, Fandral can combo with cheap Choose One cards like Wrath, Living Roots, and Raven Idol to give massive card advantage and board presence, and unlike many cards of his cost is still relevant in the endgame, capable of working with Nourish and Ancient of War. Druid's mana acceleration abilities (like Innervate, Wild Growth etc.) make him even stronger, because they do the crazy crap sooner than most decks will be able to handle, and with proper execution and luck, can allow his owner to play 7 cards at once as early as turn 3. The 2017 rotation massively reduced his power, but he's still quite handy.
  • Flamewreathed Faceless, a 4 mana 7/7 Shaman minion with 2 mana Overload, quickly became this within weeks of the expansion. The sheer tempo created by this minion along with the nerf of Big Game Hunter to 5 mana means that the Shaman player can reliably hit the opponents face while forcing them to trade into it, or waste spell cards, if they don't want to outright lose the game without the Shaman player sacrificing anything. What's worse is that the new Standard pushes out many Neutral Taunt minions and healing while Aggro Shaman only lost Crackle, which 2 copies of this card have done more than enough to replace it. The rotation of Tunnel Trogg and Totem Golem eventually scaled down the power scale of Aggro Shaman and made this card much worse.
  • Thing From Below is a 6 mana 5/5 Shaman minion with Taunt that reduces its own cost by 1 whenever its player summons a totem throughout the game. Which is often. It is very difficult to play this card for the default cost of six due to how many powerful, low-cost totem cards there are like Totem Golem and Mana Tide Totem, making it more like a 4 mana card at most and a 0 mana card most of the time. This is without getting into the common strategy with it: Shamans are very good at making frail but massive boards with just a few cards, making it easy to bait out board clears then immediately follow it up with two Things, forcing the opponent to have yet another answer. Combined with Thunder Bluff Valiant and the aforementioned Flamewreathed Faceless, it's very easy for a Shaman to keep pumping out threats until the opponent just doesn't have answers anymore.
  • The undisputed king of the Wild format is N'Zoth, the Corrupter, a 10 mana 5/7 who summons every Deathrattle minion that died that game. While already good in Standard, capable of summoning things like Voidlord, Tirion Fordring and Cairne Bloodhoof, it gets crazy when you simply take a look at how much Deathrattle crap there is in Naxxramas and GvG. You've got, as follows: the bulky Taunt minions Sludge Belcher and Deathlord, the annoying critter spawners like Haunted Creeper and Nerubian Egg, and the infamously sticky Piloted Shredder as well as its much bigger cousins Piloted Sky Golem and Sneed's Old Shredder. A Wild N'Zoth board is nigh-impossible to deal with, to the point where even Deathwing can't save you (especially since destroying all of the revived minions simply triggers their Deathrattles all over again), and managing to get yourself out of such a situation either means you played N'Zoth yourself or you deserve a goddamn trophy.
    • A few very specific outs do exist, though. One of the possible effects from Kazakus's 10-mana potions causes a mass Polymorph, thoroughly neutralizing a N'Zoth board. Psychic Scream, introduced in Kobolds and Catacombs, shuffles away all minions, cleanly answering the N'Zoth board, though not without the risk of the N'Zoth player drawing into and playing N'Zoth again. That said, Kazakus's effect requires you to be playing a specially-crafted deck for him, and Psychic Scream is a Priest spell — for other classes that don't have access to either option, they will struggle to answer N'Zoth well.

One Night in Karazhan

Also see Spirit Claws in the Nerfed Cards section.
  • Maelstrom Portal is a 2 mana Shaman spell that deals 1 damage to all enemy minions while summoning a 1-cost minion for yourself. In theory, this card is pretty much fine; it's a buffed Arcane Explosion, which nobody plays, so what's the big deal? Well, they gave it to the one class that would commit murder to get their hands on Arcane Explosion as it is, and then they tacked a bonus effect on top of it. Shaman's worst match-up, historically, has been Zoo Warlock, a deck based on summoning a bunch of cheap minions with potent effects, stickiness, or above-curve stats. Shamans normally lacked the Area of Effect damage required to deal with the deck outside of the costly Lightning Storm and Elemental Destruction, but Maelstrom Portal is not only cheap, it summons another minion prepared to kill whatever the Zoo player plays next. Add in the on-demand spell damage through the hero power to turn it into a 2-mana Consecration and it's utility in match-ups other than Zoo, and Maelstrom Portal ended up being an auto-include from day 1.
  • Barnes was once seen as "having potential" in his debut, and since then has quickly risen to becoming one of the most hated card in the game. Barnes quickly rose to fame in Knights of the Frozen Throne in Resurrect Priest decks, summoning Obsidian Statues and The Lich King on turn 4, where once they are killed the Priest is free to resurrect them with Eternal Servitude for full stats on the next turn. While it was initially overshadowed by Highlander Priest before its nerf, Kobolds and Catacombs made things even worse by adding an even bigger form of resurrection via Lesser Diamond Spellstone. The main problem with Barnes is that there are very limited ways to get big minions out earlier for Priests otherwise; every other card options can be played a Turn 6 at best; Barnes can be played at Turn 4 and invalidates the main weakness of an otherwise slow deck. Even after One Night in Karazhan was rotated out, Resurrect Priest remains the scourge of Wild, where it has access to more archetype supporting cards and even better high-cost minions.
    • Barnes is even more polarizing in another type of deck, one where the only minions on the deck is Barnes and Y'Shaarj. Its entire gameplan involved playing Barnes to get a 1/1 Y'Shaarj, which pulls the original Y'Shaarj from the deck. Of course having no other minions meant you have to rely purely on spells alone until you drew Barnes, so even when this combo was possible from his debut it was a gimmicky deck at best... until Blizzard created a deck that just so happens to run completely on spells: Spell Hunter in Kobolds and Catacombs. Spell Hunter had plenty of token generating cards to work with to survive even without drawing Barnes on Turn 4, and even if it blocked To My Side! and Rhok'delar, the cards that actually incentivized running the deck, it was just icing on the cake after you played Barnes. Most decks have no way to deal with a 10/10 that early, so it's easy to see why some people would straight-up concede when they see a Hunter play Barnes on curve (or on the flip side, concede if they draw Y'Shaarj).

Mean Streets of Gadgetzan

Also see Patches the Pirate, Small-Time Buccaneer, and Raza the Chained in the Nerfed Cards section.
  • Jade Idol. It's a 1 mana Druid spell that either summons a Jade Golem or shuffles 3 more Idols into the deck. The deck that uses it, Jade Druid, isn't particularly good, but it had a nightmarish side-effect on both the Gadgetzan and Un'Goro metagames - it removed anti-aggro control decks from the game singlehandedly. This caused the meta to twist and churl until only decks that were faster than Jade remained - even the control decks needed to be proactive in the lategame instead of just turtling, meaning their aggro match-ups became weaker. This eventually got so frustrating that Blizzard themselves got fed up with it and printed the Skulking Geist in Knights of the Frozen Throne, a 4/6 for 6 mana that destroys all 1-mana spells in both hands and decks. All of them. While Geist proved to be a reliable answer to Jade Idol in slower decks, its presence didn't completely dissuade Jade Druid from the ladder.
  • The Drakonid Operative can be quite the game-ender. It's a 5 mana 5/6 Priest Dragon that, if you're holding a dragon, Discovers a card in the opponent's deck. In addition to giving you a free card, an edge in the fatigue game, and information about what your opponent isn't currently holding, this can allow you to pick up very powerful cards because, unlike other Discover cards, this one is guaranteed to only pull good cards. Cards like, as follows: your opponent's Drakonid Operative, which can create an endless train of Operatives, big-time legendaries like Ragnaros or Reno Jackson, burn spells that Priest usually isn't allowed to have like Fireball, nasty survival tools like Ice Block and major lategame winners like Anyfin Can Happen, which can turn your opponents' stratagems against them. It's especially nasty when combined with Brann Bronzebeard, letting you take another look at their deck for information and taking whatever you please. Drakonid Operative is so powerful that he, Netherspite Historian and the newly introduced Primordial Drake essentially carried Dragon Priest into the meta of the Year of the Mammoth despite rotation causing Dragon Priest to lose a lot of vital cards.
  • Kazakus, a 4 mana 3/3 Kabal note  minion. If the player has no duplicates in their deck at the time of his summoning, Kazakus allows his owner to build a custom spell that can cost 1, 5, or 10 mana with 2 effects of correlating power. The sheer amount of abilities the potion can have is astronomical, which makes it complicated to explain, but the basic gist is that Kazakus' potion can be a board clear+heal, a damage spell with a fat demon attached, a N'Zoth that draws cards, or basically anything else, all of which are undercosted. The flexibility is utterly insane, with the only tradeoff being the somewhat RNG nature of the choices. It gets outright nightmarish when combined with Brann Bronzebeard, allowing the player to get another freaking spell, almost guaranteeing victory because not even the RNG aspect can balance it out; by getting 2 Kazakus spells, the odds of obtaining potions you actually want goes up.

    Year of the Mammoth 

Journey to Un'goro

Also see The Caverns Below (twice) in the Nerfed Cards section.
  • Primordial Glyph is a 2 mana Mage spell that Discovers a spell and reduces its cost by 2. The fact that it Discovers the spell is a huge deal, because you can just go digging for burn damage, removal, or defenses on a whim, and the sheer quality of Mage spells as a whole means that it's difficult to be mad with whatever you get. Additionally, the cost reduction negates the main weakness of expensive Mage spells, because now you can actually play more cards in the same turn you nuke the opponents board with a Flamestrike or a Meteor. It gets disgusting in the event you pull a card that's already efficient like Fireball, which can set up some nasty burst combos. In rare cases, and if the other two spells were not to your liking, you could discover another Primordial Glyph which gets reduced to free for another shot at getting what you want, or to proc another effect that requires a spell being cast, like that of Mana Wyrm or Open the Waygate.
  • Sunkeeper Tarim, a 6 mana 3/7 Paladin Legendary minion with Taunt and the effect of turning every other minion on the field to a 3/3. This card is absolutely bonkers on its own with the Paladin's playstyle of summoning tokens and controlling the board, since it allows even the humble Silver Hand Recruits to now trade evenly with formerly giant minions. What pushes it into broken status is its absolutely insane synergy with the Murloc package. Murloc Warleader's buff is continuous so it will not be overwritten by Tarim's stat-altering ability, turning a swarm of mere 1/1 Murloc tokens into a wave of fearsome 5/4 beaters. The fact that he has Taunt lets your Murlocs survive another turn, enough for you to drop a Gentle Megasaur to adapt the Murlocs and crush the opponent. It's no wonder that he saw play in almost every viable Paladin deck along with Tirion (see Classic).
    • Despite the fact that the Murloc package became less popular after the Warleader nerf, there's no ignoring the fact that Tarim's stats paired with his Taunt ability and universal stat-altering ensures that the opponent will have to expend three minions to take care of him, excluding external assistance. A near-guaranteed 3-for-1 trade on his own is good enough to warrant constructed use wherever he can be run, especially if he defeats things like three giant Jade Golems on his own.
  • What makes Stonehill Defender so popular is what its Discover mechanic can do. Although there's plenty of minions with Taunt that can cause it to whiff at times, other times you could simply luck out and pull high-impact minions, and the card quality just got even better with subsequent sets. Such high-rolls include Rin or Voidlord for Warlock, Obsidian Statue for Priest, the aforementioned Tirion or Tarim for Paladin, or The Lich King for anyone.
    • Is your opponent playing Odd Paladin, and thus cannot put Tirion, Tarim, or the Lich King in their deck? You're still not safe from Stonehill Defender Discovering them.

Knights of the Frozen Throne

Also see Spreading Plague, Bonemare, Saronite Chain Gang, and Leeching Poison in the Nerfed Cards section.
  • Initially written off as being too slow to be worth the effort, Hadronox made a huge comeback in the Year of the Raven as the centerpiece of Taunt Druid. This 9-mana 3/7 spider has the powerful Deathrattle of resummoning every Taunt minion that died under his owner's control that game, allowing Druids to build huge Taunt walls that usually require a complete board wipe to get past, and since it requires the Druid to run a ton of Taunt minions, they'll usually have no problem reaching the late game. Saving a silence for Hadronox? Won't work, because the Druid will immediately Naturalize Hadronox to deny you the chance. However, what really pushed Hadronox over the edge is Witching Hour, which allows the Druid to resurrect him up to twice, and Carnivorous Cube, which allows you to duplicate Hadronox while setting off his Deathrattle. The main weakness of the deck is cards that put Beasts on the opponent's board like Hex, Polymorph, and Cornered Sentry, as these can cause Witching Hour to fizzle, but if you're not playing Mage, Shaman, or Warrior, tough luck. Some players that use other classes have resorted to teching in Tinkmaster Overspark of all cards just to neutralize Taunt Druid.
  • The most reviled card in the expansion easily goes to Ultimate Infestation, a 10-mana Druid spell that deals 5 damage, summons a 5/5, gives the Druid 5 armor, and draws 5 cards. If you do the math, that's roughly 17 mana worth of value packaged into a single card.note  The main weakness of the grindy Jade Druid was that it, too, eventually runs out of steam without something like Gadgetzan Auctioneer to combo with Jade Idols, but Ultimate Infestation generally remedies that, on top of creating a board swing and giving extra armor to extend the Druid's stamina. Even after the Jades rotated out, Ultimate Infestation was still a guaranteed two-of for every single Druid deck just because of how utterly obscene it is, even though you'd realistically only ever use one.
    • The insanity got worse in the Standard Blood Magic brawl, where you can cast spells with health as opposed to mana. Ultimate Infestation on turn 1 was not a pretty sight, especially when the armor it bestows allows the Druid to throw out a few more spells without endangering his health.
  • The Death Knight Hero Cards were the first of their kind in the game, which naturally led to them warping the meta around themselves. For the entirety of their run in Standard and continuing into Wild, many decks hinge on the powerful Battlecries and upgraded Hero Powers they offer to win the late game, because the majority of them generate insane value the longer the game goes on, letting their user easily outlast opponents. Of course, some of them made a bigger splash than others:
    • Shadowreaper Anduin, an 8 mana Priest Hero card that kills all minions with 5 attack or more and changes the Hero Power to Voidform - a Hero Power that deals 2 damage and then refreshes itself whenever the Priest player plays a card. Sounds fair on paper, but the Hero Power has insane synergy with Raza the Chained, a 5 mana Legendary minion which allows the Hero Power to cost 0 for the rest of the game if your deck has no duplicates, suddenly allows the Priest to pump out 6-8 control damage every single turn for 0 mana. Things get even more absurd when you throw in Lyra the Sunshard and a Radiant Elemental or two, allowing the Priest to cycle through spells and damage until either the timer runs out or the opponent's health does. The fact that this card fills in two holes of Priest in one fell swoop, namely the ability to end the game through the insane amount of damage every single turn with Raza and deal with many big minions since Lightbomb rotated out, led him to cause chaos in both Standard and Wild and Priest - a class has traditionally struggled, suddenly pushed to prominence through this synergy alone. If Spreading Plague and Ultimate Infestation took the silver and gold medal for most powerful cards this expansion, Shadowreaper Anduin took the bronze for his synergy with Raza. This eventually lead to Raza being nerfed to only reduce the cost to 1, severely limiting the deck's burst output.
    • Initially, Deathstalker Rexxar wasn't hated as much — its Zombeast mechanic was innovative and actually gave the normally glassy Hunter class access to lategame value. However, as the times went on and more Beasts and keywords were added, there were ways to grant Zombeasts Rush, Lifesteal, Poisonous, etc. Deathstalker Rexxar became a powerful instant-include to nearly any Hunter deck, turning Hunter into a sense Master of All by the end of 2018 — the deck's own base cards provide enough aggression to rush down slower opponents, while Deathstalker Rexxar's boardwipe Battlecry and Zombeast value can let the deck outgrind more aggressive opponents.
    • Frost Lich Jaina quickly became the Holy Grail of Control Mage decks everywhere. While her high cost of 9 mana means that playing her causes you to fall behind on the board, being able to convert minions into Water Elementals with Lifesteal means that you have about three turns at most to capitalize on this before she starts inevitably out-grinding you. The threat of Jaina's hero power makes playing minions inherently risky lest they be turned into beefy meat-shields that Freeze enemies, making it even harder to trade favorably and nigh-impossible to push in face damage, and since the Lifesteal applies to all Elementals, cards like Ragnaros and Baron Geddon become exponentially more threatening as their high-damage abilities also heal Jaina for a huge amount. Not only did this make Frost Lich Jaina great for stalling out until you drew your win condition, she's good enough to use as a primary or alternate win condition on her own.
    • Bloodreaver Gul'dan swiftly achieved infamy for rendering Lord Jaraxxus, long considered one of the better Classic and Warlock Legendaries, completely obsolete. His Battlecry effect is effectively a N'zoth for Demons, and given the decks Warlock was running at the time, this often included several angry Doomguards ready to rip the opponent a new one, protected from retaliation by Voidlords and other Taunts, and while Even Warlock had neither of the above, it had enough alternative options to make the Battlecry worth the 10 mana cost. His Hero Power is no slouch either, providing Gul'dan with a steady stream of healing to keep him healthy in the late game while doubling as efficient removal, letting him comfortably sit back and watch the opponent slowly bleed out.

Kobolds & Catacombs

Also see Corridor Creeper, Call to Arms, Dark Pact, Possessed Lackey, Spiteful Summoner, Level Up!, and Lesser Emerald Spellstone in the Nerfed Cards section.
  • Duskbreaker, a 4 mana 3/3 Priest Dragon that deal 3 damage to all minions if you're holding a Dragon. It's hands down one of the most powerful anti-aggro tools available to Priest, and an absolute godsend to a class that's inherently weak to early-game pressure, letting you crush entire boards of weenies while leaving a 3/3 ready to trade with whatever the opponent plays next. Furthermore, as a Dragon, it can be Discovered from the effect of Netherspite Historian. This allows the Priest to have Duskbreaker handy more consistently at the right time, on top of serving as extra copies of its board clear. After the Raza nerf, this card, combined with other powerful dragons like Drakonid Operative and Cobalt Scalebane, is what kept Priest relevant, as Duskbreaker was extremely handy in crushing the Zerg Rush tactics of Aggro Paladin. Even after the Year of the Raven rotation, which took out a lot of Dragon Priest cards, many Priest decks still run a handful of Dragons just so they can use Duskbreaker.
  • Kingsbane, a Legendary weapon for Rogue that starts off as a 1/3 but keeps all enhancements given to it, and has a Deathrattle where it shuffles itself back into the deck. While it made ripples in Standard while Coldlight Oracle was still around, it really became obscene in Wild Mode. In addition to the full spectrum of weapon-buffing cards available to Rogue, Wild includes Gang Up, a must-have for any mill deck to duplicate your Coldlight Oracles. Thanks to Leeching Poison giving Kingsbane Lifesteal and Valeera the Hollow allowing you to shuffle an extra copy of Kingsbane into your deck, the Rogue can rarely take damage and will never fatigue.
    • This got a lot more balanced after Rastakhan's Rumble, which severely nerfed Leeching Poison to only last a single turn.
  • Voidlord, a 9 mana 3/9 Warlock Demon with Taunt that summons three Voidwalkers when it dies. This fat-ass of a minion forces your opponent to sink a minimum of 18 damage to break through it, making it great for stalling for time — barring Silence/transform effects or a very clever use of Defile, it takes a lot of resources to break past this wall. On its own, it'd be balanced due to its high mana cost, but Kobolds also introduced Skull of the Man'ari and Possessed Lackey to cheat it out from the hand and deck respectively, allowing Warlocks to effortlessly reach the lategame. It also has synergy with Carnivorous Cube, which can eat the Voidlord and then summon two more copies of it, and Bloodreaver Gul'dan, who can summon Voidlord and the Voidwalkers to form an unstoppable Taunt wall. It being a Deathrattle minion also results in crazy value with N'Zoth. This card was so oppressive that Spellbreaker and Harrison Jones went from rarely-seen tech cards to main-deck staples, simply because not having answers to a turn 6 Voidlord meant that you'll probably get crushed by the enemy Warlock in short order.
  • Carnivorous Cube is a 5 mana 4/6 that eats one of your minions as its Battlecry and summons two copies of it as its Deathrattle. When you build your deck around that, it's hands-down the best combo-enabler in the game. Not only does it duplicate minions, it triggers Deathrattles and works with Deathrattle synergies itself. Unlike other combo cards, it has an insane amount of versatility with how you use it in your combo. You can use it to clone Voidlords, triple up on charge minions for crazy burst, create walls of 3/12 Taunts, trigger Kathrena Winterwisp or Silver Vanguard in a pinch, trigger and clone Hadronox, and so much more. That, and eating even a medium minion puts a ridiculous amount of stats out, like a Savannah Highmane on crack, never mind what else those summoned minions might do. The line between Control/Midrange and traditional Combo decks blurred a lot thanks to this card, just because combos became so consistent.

    Year of the Raven 

The Witchwood

Also see Genn Greymane, Baku the Mooneater, and all related synergy cards in the Hall of Fame.
  • Shudderwock, the Shaman Legendary for the Witchwood expansion. It wasn't necessarily broken in power level, but rather it literally broke the game, causing upwards of 20 minute turns. Combined with Saronite Chain Gang and Grumble, Worldshaker, Shudderwock can bounce itself into your hand endlessly, allowing you to play many of them in one turn, playing through every previous Battlecry every time. Made worse with Murmuring Elemental played before it, which doubles the Battlecry effect! It doesn't hurt that the card itself is actually pretty strong, meaning it sees plenty of play (although the full OTK deck is quite gimmicky). A month after its release, it was very mildly nerfed to only copy 20 Battlecries at a time, greatly limiting its OTK potential and absurd turn timer, but not affecting its general utility.
    • Even after the nerf and without the gimmicky OTK, Shudderwock sits at the heart of one of the most powerful combo decks in the history of the game. With Grumble and Saronite Chain Gang, Shudderwock effectively becomes a Hopeless Boss Fight once it hits the field; combined with Hagatha the Witch for board clear and Lifedrinker, and you basically get an infinite supply of Twisting Nethers, face damage, and healing. The only real counterplay to this is to either kill the Shaman before they play Shudderwock, or hit them with an OTK combo; otherwise, you might as well hit that Concede button. To give you an idea of how powerful this card is, Shudderwock single-handedly killed off nearly every other control deck in Standard format and transformed the Witchwood meta into nothing but tempo and combo decks.
    • Eventually it got so bad Blizzard axed the concept, changing Saronite Chain Gang to summon another Saronite Chain Gang instead of a copy of itself. The combo could still be done in Wild with Dopplegangster, but that requires putting a bad card in your deck, making it significantly weaker.

The Boomsday Project

Also see Giggling Inventor and Reckless Experimenter in the Nerfed Cards section.
  • When Juicy Psychmelon (a cheaper Sprint that tutors) was revealed, many players cried out how Druid, the best and most efficient combo class, was being given another ridiculous consistency boost. While those fears ended up being unfounded in Standard, it's a different story entirely in Wild. Combo Druid (of many varieties) went from the best Wild deck to the only Wild deck, able to draw its combo enablers every game and blow anything slower away. With the class's mana ramping, it can draw into and play out a game-winning combo before most other decks have a chance to react. Throw in the extreme armor Druid can build up, and they're not even weak to aggro. Juicy Psychmelon was the final tool to fully round out the overbloated class. This was eventually lessened when Aviana was nerfed to 10 mana, preventing her from being drawn alongside Kun.
  • While Dr. Boom, Mad Genius wasn't regarded the strongest Hero Card (although it was still considered a step up from Scourgelord Garrosh, which was played pretty much solely for his Battlecry and nothing else), its real power became far more apparent after the Year of the Dragon rotation, whereupon it became one of only three Hero Cards left in Standard. It's played in every Warrior deck without question, providing a huge armor boon mixed with strong hero powers (some minor unreliability notwithstanding) and a game-warping passive that turns mechs - already strong on their own - into board controlling nightmares. If your opponent plays Dr. Boom on turn 6 or 7, it might as well be game over as they bulk up from constant 7 armor, board clears, and free mechs for the rest of the game. Even compared to Hagatha and Zul'jin, Boom is without a doubt the most terrifying Hero left standing.
  • Zilliax, the card that has it all. A combination of incredible defensive keywords and just enough stats to make an impact on the board even after your turn passes makes Zilliax one of the strongest Legendaries in the game. No Control or Midrange deck would be complete without him. Additionally, his wide range of effects as well as being a Mech make him easily drawn by tutors and created from multiple cards for free. It should be telling that - despite being the flagship Magnetic card - Magnetic is usually his least important ability.

Rastakhan's Rumble

Also see Raiding Party in the Nerfed Cards section.
  • Master's Call is an incredible refueling card for Hunter. For 3 mana it lets you Discover and draw a minion in your deck - but if all three choices were Beasts, you instead draw all three. While that sounds like an RNG-heavy effect, you can negate it completely by building a deck that's all Beasts and spells. Hunters have access to the best Beasts in the game as well as high Beast synergy, so the downside is hardly a downside at all. What's more, the card has synergy with Dire Frenzy, drawing the copies created more reliably, as well as Zul'jin, who recasts your spells for even more value. It gives Hunter an insane aggressive backbone that can push into the late game, even without Deathstalker Rexxar.
  • Da Undatakah is a 8 mana minion who gains the Deathrattle of 3 minions that died this game. Give him Immortal Prelate's and Silver Vanguard's Deathrattles and give him Taunt through Sunfury Protector, and what do you get? A Taunt minion that instantly resummons itself on death. Without any Silence or Transform effects, it is unlikely you will ever get past this undying wall.
    • Da Undatakah also proved his worth in Druid, where he became a handy addition to Taunt Druid's lineup. By combining it with Hadronox and Astral Tiger, Undatakah can resurrect a bunch of Taunt minions and then reshuffle himself into the deck to do it again later. Chances are, the opponent will eventually run out of answers after getting wave after wave of Taunts thrown at them, and unlike Hadronox itself, Undatakah doesn't get crippled by the enemy summoning Beasts on your board to mess with Witching Hour.


    Year of the Dragon 

Rise of Shadows

Also see Archivist Elysiana and EVIL Miscreant in the Nerf Cards section.
  • Conjurer's Calling is a 3-mana Mage spell that destroys a minion and summons two minions with the same cost to replace it. If you use it on a 4-mana minion, that's already a 1 mana bonus value, and if you use it on a 10-mana minion, that's 7 mana bonus value. But this card really becomes a Game-Breaker when used on Mountain Giant, basically turning it into a discount Faceless Manipulator due to the lack of other 12-mana minions. Considering Mountain Giant can be played as early as turn 3 note , if the enemy does not kill that single Giant, it can go out of control starting next turn and seal the game, doubly (literally!) worse when enemy Khadgar is on the field. It doesn't help that it can summon a Grave Horror instead, the only other 12-cost minion in Standard, and make things even more troublesome with its Taunt. And as the cherry on top, it has Twinspell, meaning you effectively have four copies of it in your deck.
  • Mana Cyclone is a 2-mana 2/2 Mage Elemental with the Battlecry that generate a random Mage spells for each spells you played this turn. As if being a 2-mana pseudo Lyra isn't enough, this card not only allows the Mage to keep their hand count for cards like Mountain Giant and Twilight Drake as well as allowing them to use their spells without worrying about running out of resources, it can be combo with Elemental Evocation for a disgusting 0-mana and a free extra spells. And that not mentioning the disgusting possibility of high-rolling from this card, allowing the Mage to potentially generate board clear, another copies of their Freeze effects to further stall out the game, or another copies of Conjurer's Calling.

Arena has some too, but as expansions are added to the game they become less cosmically destructive, not because they're getting nerfed or anything but because more cards means a wider card pool for the draft to pick from. Due to the Arena pool conforming to what's available in Standard, anything that's rotated out would not be available outside of Wild Arenas, and even so, the expanding card pool reduces the chance of finding these cards.
  • Mage has been one of the best classes to take into Arena due to the amount of card generating effects available to the class. Add to the fact that these cards were random or Discovered and nobody could play around what had been generated. Between Cabalist's Tome, Babbling Book, Primordial Glyph, and Shimmering Tempest, a Mage could conveniently get the spell they need to stage a turnaround or secure their victory. In fact, a few Mage cards on their own are Arena Game Breakers, which adds to the frustration when one discovers them:
    • Flamestrike again, but for reasons on top of the ridiculous value it already provides. It's a common, meaning that it's very unlikely for someone to go through a Mage draft without seeing it, and the nature of Arena (trading minions and focusing on value and tempo) means that it's almost impossible not to get good use out of it. More importantly, it's possible to have more than two, meaning that with a good draft you'll have free area damage on tap prepared to eliminate anything in your way. Flamestrike was subsequently made to appear in Arena drafts 50% less frequently.
    • Firelands Portal, a 7 mana common Mage spell that summons a random 5-cost minion and deals 5 damage. Flamestrike is literally the only thing you wouldn't pick this over, and even then its a close contest. Firelands Portal's insane tempo swing from taking a minion and then playing one of your own can win a match in one fell swoop, and since it's a common you can just do it again and again until you win. Sometimes the 5-cost minion will be junk like Faceless Manipulator, but other times it'll be something revolting like Earth Elemental.
    • Meteor is a 6 mana spell that deals 15 damage to a single minion and 3 to adjacent ones. There are very few unbuffed minions that can survive a direct impact to Meteor (the Mage's Hero Power is also very good for breaking Divine Shield), turning it into effective hard removal with a chance of a 3-for-1 with unfortunate positioning. The possibility of its existence against a Mage player makes arranging your minions that more important.
  • What shot and keep Rogue into top tier in Arena and competing with Mage isn't just their mana-efficient basic and classic cards (Backstab, Eviscerate, Tomb Pillager etc.) but it is the class's Hero Power. Dagger Mastery allows the Rogue to equip a 1/2 weapon, which in Arena play is essentially 2 of the Mage's Hero Power (Fireblast) that you can control and hold back to kill or weaken a minion in a game mode that focuses on keeping minions alive get more favorable trades. This Hero Power is so broken that many Rogue Arena decks tend to draft less 2 mana minions than other classes because their turn 2 play is usually Dagger Mastery to kill a 1-drop and save their card slots for better options.
    • Envenom Weapon is one of Rogue's strongest cards in Arena — giving their weapon Poisonous turns their already good Hero Power into 2 charges of hard removal, perfect for taking out even the toughest Taunt minions to either push damage or trade better using their other minions.
    • Vilespine Slayer gave every single already powerful Rogue card a run for their money. It's a 5 mana Assassinate (already a very powerful card) with a 3/4 body with the only condition is that you have to combo it - something Rogue can easily do with cheap cards.
  • Kel'Thuzad was insane for the longest time. In constructed, having a developed board either means you're playing an aggro deck or you were already winning, meaning Kel'Thuzad usually only sees play in Druid decks, which can reliably have a big minion on the board prepared for him to resurrect, and deathrattle Shaman which is focused on duplicating him with Reincarnate. Arena is different; both sides will almost always have some minions in play with complete resets being rare, a situation which is utterly pristine for card based around having a board. Indeed, dropping Kel'Thuzad was a death sentence for the opponent, as the astronomical board advantage meant that not even the ever feared Flamestrike could stop him. He got much less effective as Arena became faster with the addition of more cheap minions, but even still most people will take Kel'Thuzad the second he shows up.
  • Murloc Knight was once the main reason for Paladin's popularity in Arena. It's a 3/4 for 4 with the inspire effect of summoning a random murloc. In constructed, it's the most popular inspire minion because of its potential to summon something scary like Murloc Warleader, Old Murk-Eye, or another Murloc Knight, mainly held back by its overcrowded mana slot and high potential to whiff. In Arena, removal is much more sparse, meaning that Murloc Knight will likely stick around long enough to pop multiple times, almost assuring board control in a game mode defined by board control. Most importantly, it's common, meaning it's very hard not to get one during a draft. It got so bad Blizzard directly introduced two lowly statted murlocs in League of Explorers just to nerf it, and has steadily received more nerfs over time, making it much less powerful.
  • Murloc Knight's torch was passed on to Keeper of Uldaman, a 4 mana 3/4 Paladin minion that changes the stats of a minion to 3/3. Remember how Paladin didn't have hard removal? Well then this'll be weird, because now they can handle any big minions thrown their way, when previously they were restricted to just lowering its attack without actually clearing it. Not only can Keeper kill the affected minion without dying, she can also buff her allies as well, granting even a lowly Silver Hand Recruit +2/+2.
  • Abyssal Enforcer, a 7 mana 6/6 Common Warlock Demon that deals 3 damage to all other characters. It's a Flamestrike with a huge body attached, and while it damages its allies as wellnote , that doesn't matter that much when everything that can fight with it is dead, allowing the Enforcer to slaughter anything that drops next or mash face until the opponent answers it. It cannot be understated how outrageously powerful this card is; Warlock, previously one of Arena's joke classes, instantly upgraded to the number one slot just because of this powerhouse, and getting enough of them generally guarantees the 12 wins reward. The dominance of Abyssal Enforcer eventually led to it being made 50% less likely to appear in an Arena draft.
  • Vicious Fledgling earned the nickname of "Dr. 3", taking after Mysterious Challenger and Dr. Boom. This 3/3 for 3 mana adapts each time it hits the enemy hero — and if it gets Windfury it gets another swing for another adaptation, quickly spiraling out of control as it accumulates more and more buffs. Due to Arena's lack of efficient removal, if you can't get a Taunt in the way so that you can clean up the Fledgling through combat damage, the Fledgling can singlehandedly cause an Arena loss. The more infuriating part is that this is a neutral minion so no matter what class you're up against there's always a chance the opponent has it. A patch has reduced the chance of Fledgling appearing in a draft, but eventually they went so far as to outright ban Vicious Fledgling from Arena, meaning it won't show up in any draft.
  • Spikeridged Steed is a 6-mana Paladin spell that gives a minion +2/+6 and Taunt, while also causing them to leave behind a 2/6 with Taunt if they die. Essentially, turning any minion of your choice into a stronger version of the infamously sticky Sludge Belcher. Using it even on a simple 1/1 creates a wall capable of soaking at least 13 damage; using it on anything larger lets them survive through troublesome trades.
  • The Death Knight cards of the Knights of the Frozen Throne expansion open up drastically new playstyles in constructed. In Arena, though, they are absolutely game-changing and can be the sole cause of a player turning the game around. Their Legendary rarity reduces the rate at which a player might be able to encounter them, but there's nothing stopping them from Discovering a Death Knight card. The ability for the Death Knights to win games alone resulted in them being removed from the Arena draft pool, though the chance of Discovering a Death Knight card is still a notable, if incredibly rare, danger.
  • Mind Control Tech is a 3 mana 3/3 whose Battlecry takes control of a random enemy minion if the opponent controls 4 minions or more. In a game mode where board presence is everything, a neutral card that punishes the opponent for playing a bunch of minions is an easy auto-pick for every class and can easily result in a powerful swing in your favor, forcing players to constantly tiptoe around the effect. Furthermore, the RNG nature of the card naturally has the potential for much frustration, whether it's by stealing the opponent's best minions against all odds or by taking a Silver Hand Recruit among bigger minions. Due to MC Tech's potential for creating an all-round un-fun experience, it was given the boot from Arena mode.

Arena Events

In addition to the normal Arena mode, Blizzard occasionally hosts Arena Events, ranging from duo-class arenas, Wild arena, and limited time arena-exclusive cards. Each of them break the game in their own way (on purpose, of course), but these are the outliers.

Taverns of Time

  • In a set of purposefully absurd cards, Cavern Dreamer is the king of BS. A 2 mana 1/3 Mage minion, it adds a random spell from any class that costs 2 or less to your hand at the end of your turn. Every turn. While there are a handful of whiffs, more often than it generates a valuable spell. Since spells harder to come by, even just one tick is strong. Due to the lack of removal in Arena and the Dreamer's decent health, it's almost guaranteed to stick around for several turns. In fact, many cheap spells are removal, meaning it might generate a card to protect itself. On top of that, Taverns of Time cards have a huge occurrence bonus, meaning the Mage probably has two or three of these in their deck.
  • Wildlands Adventurer is a 5 mana 5/5 that adds a random Hall of Fame card to your hand. The card itself is very strong, having near-premium stats and a card draw effect to boot. What gets really crazy is when it gives you Sylvanas or Ragnaros. Those two were Hall of Famed for a reason, and are even more powerful in Arena. While the Hall of Fame has some serious misses, the chance to land on those along with the great stats easily puts the card here.
  • Chromie is one of the two Legendaries from the set, so she doesn't show up in too many drafts. When she does show up however? Her Battlecry shuffles four Epochs into your deck, based on various Caverns of Time instances. The epochs give your minions +2/+2, deal 2 damage to all enemies, give you two random spells, or give you two random Legendaries. The catch? They're casted for free when drawn. That's a free Consecrate, a free Wisps of the Old Gods, and two free pseudo-Thoughtsteals. While it's a bit inconsistent, having a board state where the cards whiff is pretty rare in arena. You throw down Chromie, and she suddenly generates insane power spikes for free throughout the game.

    Singleplayer Content 



  • Any A.I. Breaker immediately falls into this. By exploiting Artificial Stupidity, hard fights can suddenly become a breeze. The most infamous example is a combination of Kel'Thuzad and any large taunt minion. As long it has enough health to withstand the opponent's board, the AI refuses to kill the taunt, reasoning that it will just come back and waste their minions. With a full board of minions, this can lock many bosses up and prevent them from taking any actions until they draw hard removal for KT. Another big example is Rafaam turning himself into Lord Jaraxxus and casting Sacrificial Pact on himself. The AI is loosely programmed to use any card in the game, and it recognizes that Sac Pac has a target that isn't a friendly minion, killing itself.
  • New card releases. Encounters are designed with a certain card pool in mind, and often have ways to avoid things that would ruin them. However, new cards introduce things that old fights never were ready for. One of the oldest examples is Patchwerk, initially a tank-and-spank simulation that was trivialized by Jeeves, which forced him to draw deep into fatigue every turn. Arguably, this is the reason for One Night In Karazhan's lukewarm difficulty; it wasn't designed around the greatly expanded card pool. This is one possible reason to why later single-player content switched to draft-like modes where your deck isn't built from your collection.
  • Majordomo Executus is a card famed, or rather infamous, for being not very good. On death, Executus will replace your hero with an 8 HP Ragnaros, and a Hero Power that deals 8 damage to a random enemy, which is comically awful, as you'll likely die before the Hero Power is capable of overwhelming the enemy. If Executus is given to a boss, however, he will drastically cut down their usually massive HP pool. True, you still need to put up with Rag's Hero Power, but on Heroic his power will almost certainly be weaker than what they had before. The only real restriction is that you need a way to give him to the boss, but a surprising amount of foes have ways to take control of or gain copies of your minions, most notably Heroic Kel'thuzad and the Paladin version of the Lich King fight.


Due to how these game modes are designed to emulate a Roguelike, there's definitely a chance you gather a combination of cards that will easily trivialize most obstacles you face. The biggest ones come in the form of the Purposely Overpowered treasures you discover during a run.


  • The Potion of Vitality is a useful little treasure that passively doubles your HP every game. It can buy you time, give you a little extra endurance if you picked a fragile class like Rogue or Hunter, and short of an unlucky run in with a certain boss, is usually a solid pick. But through luck, it's possible to find two of them, doubling your already doubled HP! By the final boss, you'll be going in with 200 HP, making victory much more likely, if not certain. You can even defeat the final bosses through fatigue. It gets better if you were lucky enough to draft Reno Jackson and/or the below-mentioned Wish - on the off chance the boss starts tearing through your monstrous health, you can just heal back to full HP.
    • For extra fun, combine Potion of Vitality with Cloak of Invisibility. These two treasures effectively cancel out each other's weaknesses, giving you a nigh-invulnerable board and more health than the bosses you're facing and more or less throwing the difficulty curve out the window.
  • Captured Flag offers a humble +1/+1 buff to all your minions. This buff easily becomes vital for any Zerg Rush build, as your humble 1/1 minions become twice as tough and can get a lot of damage in if summoned early, and everything else has strength on par with minions of 1 cost higher. Note that also works on summoned minions, meaning Paladin creates 2/2 tokens with their hero power, or other crazy shenanigans.

Dungeon Run

  • Justicar's Ring upgrades your Hero Power and also halves its cost. This has a most profound effect for Warriors and Priests, giving them the ability to get absurd amounts of armor or heal off large amounts of damage for very little mana. Paladins also benefit greatly, as they get a guaranteed decent turn 1 and 2, and can build up lots of Silver Hand support cards to abuse it. Even with other classes, the upgraded Hero Power is still good for pressuring the enemy when you have loose mana to use it on.
  • The Cloak of Invisibility gives your minions permanent Stealth, letting you wail on the enemy hero with impunity. This has a drawback, though, as your Taunt minions will not be able to protect you. That's fine and all, but it gets truly absurd when you get some end-of turn effects in your deck. Suddenly, your Emperor Thaurissan is reducing the cost of your cards, your Grimestreet Enforcers are buffing all of your hand by +1/+1, and there's nothing the boss can do.
    • Maybe the most broken effect is Mal'ganis, however. Mal'ganis makes your hero Immune. With a stealthed board and an Immune hero, the boss literally can't do anything. He's found in the Demons package for Warlocks, and is often paired with Void Callers, letting you cheat him out as early as turn four. Mages can accomplish something similar with Animated Armor, forcing them to only take 1 damage at a time and greatly prolonging their survivability.
  • Wax Rager is a 5/1 minion for 3 that resummons itself on death. Essentially, you get 5 free damage every turn to splash wherever you feel like, letting you, for instance, constantly kill off Darkspawn summoned by the Darkness without needing to expend your Candles. Pair it with the aforementioned Cloak of Invisibility, and it can't even be Silenced or transformed. If you use it with Frost Lich Jaina, you not only have a great source of healing (since it's an Elemental which gives it lifesteal), you can kill it with your own Hero Power to create more Water Elementals without really losing the Rager.
    • There are several cards/passives that make Wax Rager even more downright absurd: Totem of the Dead causes your Wax Rager to multiply every time it dies, N'Zoth counts how many times your Wax Rager dies and may flood your board with copies of itnote , and having a Spiritsinger Umbra on the board when you play or kill a Wax Rager will cause the Ragers to multiplynote . Even The Darkness with its unending tide of 5/5's and Vulzstrasz and his constant bombardment can't survive the onslaught.
  • Wand of Roasting is a 10-mana spell that casts Pyroblast at random targets until a hero dies. Basically, if a boss fight is going completely south and you'll definitely lose, it's a risk-free Death-or-Glory Attack that can quite hilariously bail you out, if you're lucky.
  • On a similar note to the above is Wish, another 10 mana spell. It fully heals your hero while also filling your board with random Legendaries. You get a no-condition Reno Jackson effect on top of a bunch of probably game-winning minions.
  • The Amulet of Domination is a 2 mana spell that lets you steal an enemy minion and puts a copy of it into your deck for the rest of the run. The Magic Mirror is a 1 mana spell that does something similar, only that it makes a clone of that minion as opposed to stealing it. It's pretty convenient if you come across something that helps your game plan, but its true power comes into play if you encounter Ixlid. This boss summons a 1/1 Spore that instantly destroys any hero it touches — including the other bosses. Stealing the Spore is generally considered the easiest way to get past the final bosses, who are otherwise brutal.
  • Jade Golems and C'Thun buffers have special buckets that appear for some classes that can only give synergy cards for their respective archetypes, with no cap on how many can be put into a deck. This includes the legendaries, Aya Blackpaw and C'Thun. Simply choosing these options every time they come up can end with a deck containing 20 support cards for either one, almost assuredly resulting in a curbstomp of every boss in your way. It gets better with the Battle Totem, which passively activates all Battlecries twice - meaning double the Golems, and double the C'Thun missiles and buffs.
  • If you can get both the Blade and Hilt of Quel'Delar, it will assemble into a 1-mana 6/6 sword that deals 6 damage to all enemies every time you attack, and always appears in your opening hand. That's 12 face damage right from turn 1, good for 6 hits for a total of 72 damage. The Final Bosses of Dungeon Run have 70 HP, and though they may gain some armor through Looming Presence, you still have your minions to finish the job, especially since you've been clearing the way for them to strike.
  • If you survive Tad's onslaught of minions, he summons a Sunken Chest on his eleventh turn if he hasn't taken any damage this match. Breaking this open awards you with Tad's Pole, a 1-mana 0/1 weapon that summons minions from your opponent's deck. While whatever you'll catch may not always synergize very well with your current deck, you're still getting a minion to contest the board with and denying your opponent's resources at the same time, putting them a little closer to fatigue if you're going for that objective too. Other times you can luck out and, for instance, get Mal'Ganis from Azari's deck!
  • THE CANDLE is a 1 mana spell that deals 4 damage to all enemy minions and puts itself back into your deck after use, providing use as both a board clear and helping you outlast your opponent if you are both decked out and unable to deal damage.

Monster Hunt

  • Double Time is the holy grail of any Toki run. This passive causes the first spell of any turn to cast again with random targets. Useless for targeted damage spells like Fireball, but card generation effects like Primordial Glyph become absurd, especially since Toki can re-roll once a turn if you aren't given a desired outcome. Untargeted damage spells also become much more powerful, with special mentions going to Flamestrike, which will almost certainly destroy all enemy minions, and Greater Arcane Missiles, which deals a grand total of 18 damage. The grand prize, without question, is Time Warp, which when double-casted gives you two additional turns instead of one.
    • Even in the Final Challenge, where you have no control over the new cards you receive, Double Time continues to pull its weight. Toki's Hero card gives several decent spells that synergize wonderfully with it, like Cabalist's Tome and Arcane Missiles, while Tess's Hero Power can be used to salvage Hagatha's own Shaman spells to use against her — Who doesn't like to heal for 24 with Healing Rain? But the grand prize for synergy with Double Time would definitely go to Call of the Wild, which is a complete board flood with two of each Animal Companion!
  • Companionship, a passive exclusive to Shaw that gives his Bloodhounds an additional 2 attack. This is an immense advantage, as this turns his Hero Power into a permanent Darkbomb, allowing the player to skip out on removal in favor of card draw and board control, on top of excellent synergy with Scavenging Hyena and a few of Shaw's other unique hounds. While a second Companionship is pretty good too, the true hilarity ensues if you manage to draft Entrenchment, which grants all of your minions 2 extra health - including the Bloodhounds. Suddenly, your Hero Power can summon a 3/3 beater with Rush every turn. Companionship also makes Shaw's Nemesis fight much easier, as it allows his Bloodhounds to trade one-for-one with the boss's exclusive minions.
  • The Jade package returns as an asset for Tess. This time, though, her Scavenge Hero Power works wonders with Jade Shurikens, as once you've used even a single copy, she can continuously recycle and cast the spell to summon larger and larger Jade Golems. Coupled with Sticky Hands which reduces the cost of any card you've stolen or scavenged, and it gets even easier to summon an even larger Golem!
  • Tools of the Trade is a 2 mana spell lets Tess Discover one of three weapons, all of which give huge value by themselves. The Handgonne is a 4/2, making it terrificaly powerful for its cost, and it's the most boring of the bunch. The Blunderbuss is a 2/2 that damages adjacent minions, which works wonders for early-game board clear and can stay useful into the late game with Envenom Weapon. Meanwhile, the Stake Launcher starts as an unassuming 1/8 with Windfury, but becomes an utter monster with weapon buffs. A single Deadly Poison turns it into a discount Doomhammer, while Envenom Weapon lets you remove up to 2 minions a turn, for up to 8 uses. Now keep in mind that Tess's hero power lets you reuse weapon buffs, and you can easily build a Stake Launcher that does absurd damage with Lifesteal. And to top it off, Tools of the Trade returns itself to your hand after being cast, letting you re-equip these weapons as much as you like.
  • Auctionmaster Beardo is incredibly potent if selected while playing as Toki. His ability refreshes her free Hero Power, so if you had a spell in hand at the start of your turn, you can endlessly reroll your random results until you get what you need. The only downside is whether your patience holds out.

The Great Dalaran Heist

  • Swampqueen's Call is a 2-mana spell that transforms your minions into random legendary minions. It also is repeatable that turn (unkeyworded Echo). If you combine that with Emerald Gogglesnote  and an empty hand or a lucky reduction from the bar's Take a Chance, it will cost zero. This means that you can endlessly transform your board, hoping to roll into Charge minions like King Krush or Al'Akir, swing with them, and then reroll your transformations into more iterations of Charge minions. Barring disastrous results like having all your minions turn into The Darkness, you can pretty much deliver lethal off any board. And since this is a single-player mode, you have no time limit, so reroll to your heart's content!
  • The Robes of Gaudiness have probably the most powerful effect of any Passive: reduce the cost of your cards by half. Big spells like Power of Creation and Pyroblast or high-cost legendaries like Y'Shaarj can be cheated out as early as turn 4 or 5, generating insane value and outpacing every boss short of the final ones. The drawback of only being able to play two cards each turn doesn't matter when you can throw out undercosted, overpowered minions or spells two at a time and still have mana to spare for your Hero Power. And that not mentioning that the cost reduction on odd-cost cards are rounded down. They were so powerful, Blizzard actually cut their occurrence rate down to almost nothing, making a run with them as special as they deserve. They were so broken they broke the purposefully-broken gamemode.
  • Two words; Wonderous Wisdomball. It's a passive that "occasionally gives helpful advice"note . This ranges from mundane but probably useful (adding minions to your hand, drawing an extra card) to situational at best (pulling a Deathwing and clearing the board, transforming the minion you just played into a random Legendary) to potentially lifesaving (shuffling extra cards when your deck is empty or making your hero Immune when about to take lethal damage). Although there are instances where his "advice" ends up backstabbing the player (increasing a card's cost rather than reducing it, transforming a minion into a harmful Legendary), the positive outcomes are more numerous, and Wisdomball can and has saved several runs through his effects.
  • E.V.I.L. Propaganda has a hefty mana cost of 10, but it's well worth casting when it takes control of all your opponent's minions. It can become a lifesaver, especially when you're behind on board and struggle to take it back, and most bosses rarely have the means to recover from such a swing.
  • Stargazing discounts your Hero Power by 1 mana and lets you use it twice per turn. Depending on your Hero Power of choice, this can have some amazing implications. For instance, using it with the standard Hunter Hero Power lets you deliver 4 damage each turn, practically winning most fights with just your Hero Power alone; using it with Burning Wit lets you use it twice for free and get a lot of heavy discounts on the cards in hand. If you pick up a Death Knight card or the Prince's Ring note , that new Hero Power is also discounted and can be used twice, which has deadly applications with Bloodreaver Gul'dan or Deathstalker Rexxar.

    Tavern Brawl 
  • While Tavern Brawls encourage all kind of unique strategies, most at least have some sort of major flaw to them. That cannot be said for Yellow-Brick Brawl, where Dreadsteed cranks this Up to Eleven. He's a 4 mana 1/1 with a deathrattle that summons a new Dreadsteed on death, not so bad in standard play since each replacement Dreadsteed will lack any buffs the previous one had. In this Tavern Brawl, however, Dreadsteed is almost impossible to beat. Dorothee's effects are thus that minions to the left of her have Charge and the minions to the right of her have Taunt. This means that each and every Dreadsteed summoned will immediately be able to charge in and summon another one until your opponent's entire board is cleared. It's just as bad if Dreadsteed is put on the right, as every time the opponent kills one, another Dreadsteed with Taunt will immediately come back, making it impossible to deal any damage to the enemy hero without the use of spells or hero powers. Unless you bring alternative means to remove minions (Transforming, Shuffling, etc.) Dreadsteed is impossible to shut down.
    • Unless you have Mekgineer Thermaplugg, a 9 mana 9/7 that summons a Leper Gnome note  whenever an enemy minion dies. Basically, just place the ol' Mekgineer to the left of Dorothee and kill one of the Dreadsteeds, and watch the magic happen. note 
    • Dreadsteed did get nerfed (it now spawns a new one at the end of the turn) due to various shenanigans in constructed but that also had the side effect of making it less overpowered (but still useful) in this tavern brawl.
    • Replacing Dreadsteed in this context is Necrotic Geist. When any of your minions are killed, Necrotic Geist summons a 2/2 Ghoul in its place. It will even trigger when those Ghouls die, too. So by placing Necrotic Geist on the left of Dorothee and getting a minion killed, you can get an endless stream of 2/2 Ghouls with Charge (since Geist spawns them between it and Dorothee), letting you slaughter the opponent's entire board as long as all their minions have 2 or more power. You'll also have enough room to get at least 7 damage in with Geist itself and a Ghoul.
  • In the Spellbook Duel Tavern Brawl, players have a deck of 10 unique cards, and instead of drawing from the deck, they discover a copy of a card in their deck.note  Gnomeferatu has a Battlecry of removing the top card of the opponent's deck, which actually reduces their discover options as you play more of her. Once a player is reduced to 3 or fewer cards in their deck, a bug occurs that prevents that player from taking any action.
    • This can be countered with another Game-Breaker, Jade Idol, which in this game mode might as well read "After a bit of setup, you may turn every card you draw into a big/big Jade Golem for 1 mana each".note 
    • Predating Gnomeferatu in this regard is Deathlord + Loatheb combo. Deathlord's deathrattle ability drags a minion out of an opponent's deck into the field. In normal games this ability can backfire spectacularly, but in Spellbook Brawl, this has the effect of preventing the enemy from discovering that minion for the rest of the game. While it does take some setup due to Deathlord being more expensive than Gnomeferatu, once you drag out all your opponent's minions from the deck, they can only discover spells, at which point Loatheb's battlecry ability ensures your opponent at best can only play one weak spell per turn due to having their spell cost bumped up by 5, possibly every turn.
  • The Boss Battle Royale lets players square off against each other as a boss from the solo adventures. However, they're not perfectly balanced against each other, and some bosses just have an unfair advantage.
    • Picking Warlock lets you play as Sindragosa, and not only does she have a fairly cohesive deck built around Dragon synergies, she also has the opponent fight with 4 un-removable ice blocks clogging their field, with her Hero Power freezing over more of the board as the match goes on. The opponent would have to be really meticulous about board management to avoid instantly losing all their board space, while the Sindragosa player is free to play more threats than they can reasonably handle. When the brawl was revisited in October, Sindragosa would be nerfed — the opponent only has two ice blocks on their field, and Sindragosa cannot create more.
    • The October revisit changes the boss for Druid into King Togwaggle, whose Hero Power gives him a Purposely Overpowered treasure. Togwaggle as a boss is counterbalanced by the player having their own Treasures to use against him and occasional moments of Artificial Stupidity; here, the opponent doesn't have this mercy except for being lucky enough to draw into their boss's unique material, and a player-controlled Togwaggle will make more efficient use of his Treasures. This makes Togwaggle one of the strongest selections in the brawl barring unfortunate results off his Hero Power.
  • The Duel of the Death Knights brawl starts both players out as the Death Knight heroes of their respective class, using a randomly constructed deck. Mage ended up being six shades of broken in this brawl; the Mage Death Knight, Frost Lich Jaina, has a hero power that deals 1 damage and summons a Water Elemental if it kills something and grants all of your Elementals Lifesteal - including those Water Elementals. Simply put, you just can't out-tempo Frost Lich Jaina as she'll churn out an unending tide of 3/6s with Lifesteal that freeze everything they touch (starting as early as turn 1 if she goes second and has a Snowflipper Penguin in her hand), locking down your board while inflicting a slow, protracted demise. The brawl also leans heavily towards Knights of the Frozen Throne cards, meaning that 1-health minions like Wretched Tiller, Fallen Sun Cleric, and Shallow Gravedigger are exceptionally commonplace and can easily be converted into Water Elementals. Unsurprisingly, the brawl quickly degenerated into Jaina mirror matches and little else.
  • Spirit of the Shark turns Rogue into an absolute monster in Miniature Warfare Brawl, where all minions are 1/1 that costs a measly 1. It allows Rogues to brutally abuse powerful battlecries such as Bonemare and Fungalmancer as well as nasty Combos like Edwin Van Cleef, easily creating an unstoppable board condition by turn 3, if not flat-out OTK the opponent on that turnnote 

  • Certain unlikely card combinations can utterly break the game. Observe, what happens when you combine Mal'Ganis with Stealth, and the enemy does not have sufficient area of effect spells.note  Likewise, for the love of god, never play Millhouse Manastorm while your opponent has Archmage Antonidas on the field, because if they have a spell you will lose. note 
  • Part of the parcel of being a digital card game, the game has some nasty glitches and interactions:
    • Nozdormu's brain-breaking glitchiness came in full force with the addition of Joust during The Grand Tournament. See, whenever the "end turn" button is pressed, the animation times from the previous turn carry over into the next turn, directly affecting the amount of time a player can take on their turn. This oversight is usually exploited by playing Nozdormu, who reduces the time each player has during their turn to 15 seconds, and then playing as many overtly long animations as possible to skip their opponent's turn. Beforehand, it required a convoluted set-up and wound up being too gimmicky to be consistent. Joust cards brought this problem to the forefront; the animation that plays whenever a Joust is activated is extremely long, to the point where simply playing 1 Joust in conjunction the Nozdormu exploit was enough to skip the opponent's turn. Suddenly it became a problem, as the Nozdormu player simply had to get the bronze dragon and a single jouster in his hand to win the game. Thankfully, while Nozdormu is still infamously broken his interaction with Joust cards was patched within a day, though the previously mentioned gimmick set-up still exists.
    • On launch of League of Explorers, there was a dangerous bug with Unearthed Raptor that ended up getting its abusers a lot of free wins. Raptor, by default, is a 3 mana 3/4 that copies a friendly Deathrattle effect. When combined with Brann Bronzebeard, who triggers your Battlecry effects a second time, this can stack up for even more Deathrattles. The bug kicks in once you started using a second Raptor to dupe the effects of the first Raptor; for some reason, if you duped the Deathrattle effect enough times, the game will force a crash for the opponent (sometimes both players), giving the Rogue player a free win. It was quickly hotfixed, but it was scary time for players everywhere. You know, except the Rogues.
    • The aforementioned Fandral Staghelm (See Whispers of the Old Gods above) was also the cause of a bizarre, powerful Wild-only glitch with Dark Wispers. Dark Wispers is normally a 6 mana spell that either summons 5 1/1 Wisps or gives a minion +5/+5 and Taunt. Fandral causes it to do both, but for some reason he also removed the minion restriction, meaning the player could give himself +5/+5 and Taunt. While the Taunt and +5 health are obviously good, the extra attack was utterly ballistic, because it lasted forever. Your hero can swing for 5 damage every turn with no restrictions and maintain it during the opponents turn, meaning that any minions that attacked would take 5 damage and likely die. It was swiftly patched, for good reason. If nothing else, it was kinda cool while it lasted.
    • The Shadow Visions + Radiant Elemental loop, as discovered by Disguised Toast, is a three card combo introduced in Journey to Un'Goro consisting of two Radiant Elementals and a copy of Shadow Visions, with the other copy in the deck. Because of how animation times work in Hearthstone, a crafty player can simply play the Elementals to reduce the cost of Shadow Visions to 0, then use Visions to discover the other copy of it, then play it again and again and again. From your perspective, you're just playing the same card over and over, but from your opponent's perspective, they have to sit through a short animation of the card being played every single time. Spamming Shadow Visions enough forces your opponent to watch the animations on their turn, skipping their turn entirely. This was swiftly hotfixed, thankfully.
    • A few rare interactions with Chameleos create some interesting situations. Chameleos becomes a copy of a random card in your opponent's hand each turn, and will keep any buffs when it changes. Things get a little screwy however when it turns into a card that changes stats each turn. The stat-swap and the transform effect happen simultaneously, resulting in Chameleos becoming a new card, but with the swapped stats. That also applies to Hero Cards, resulting in heroes with permanent Attack like the Fandral bug. Of course, that's nothing when compared to in-hand buffers. Behold! The 2 billion HP hero! Not exactly a likely scenario, but the fact that it's even possible is absurd.
      • Fortunately (or unfortunately, depending on your perspective) this was fixed in The Boomsday Project when in-hand transformations caused the card to lose any buffs, probably to clean up interactions with Flobbidinous Floop.
    • The preorder for Rise of Shadows included up to two free Legendary cards from the upcoming set, as per usual. What wasn't so usual was that somehow, the free Legendaries were made available immediately after purchase. Since it was trying to give the player cards that didn't exist... some odd things happened. As showcased in this Reddit thread, one player got access to a Hero Card version of Darius Crowley (from The Witchwood's final boss) and it was fully playable. Even weirder, he managed to get Wild cards into Standard while this was in his deck. This was swiftly hotfixed, but was one of the biggest Game Breaking Bugs in Hearthstone's history while it lasted.

Example of: