Goblin Lackey, Entomb, and Frantic Search are banned in Extended. "What about Grim Monolith and Tinker?" asks a bystander. "Isn't Mirrodin supposed to be the all-artifact set?" "Meh," says R&D. "How bad could it be?" ... October: Pro Tour: Tinker is held in Tinker Orleans. Tinker Mindslaver Tinker, Rickard Osterberg, Tinker Tinker ban that f**king card Grim Monolith Tinker.
Being the first trading card game, Magic: The Gathering has a lot of Game Breakers. Part of this stems from the fact that the original editions of the game were little better than an Obvious Beta (so much so that the second release of the Limited First Edition was named "Limited Edition Beta", with the first being "Limited Edition Alpha"); indeed, like most games that are played extensively, the lion's share of Game Breakers are discovered by players post-release. But the fact that Wizards of the Coast keep trying new things can't help. (Well, it does make the game more fun; we're just talking about the inevitable impact on game balance.)
The most famous of these are the Power Nine, from Limited Edition, which are banned in every format except Vintage, where they're restricted to one per deck:
Black Lotus is the Holy Grail of Magic cards. A genuine Black Lotus costs thousands of dollars with high-grade Black Lotuses from the alpha release selling for tens of thousands. Rarity is only part of the reason for the value; the sheer power of the card drives its value just as much. In a game where mana is everything, three mana of any colour you like for nothing is essentially massive Sequence Breaking. It may not be the most powerful card in the game but the fact that it lets you get powerful cards out so quickly means there is essentially no deck that would not be improved by a Black Lotus. It's so powerful that a card that does exactly one third of what Black Lotus does had to be banned. It's so powerful that a version that requires you to throw your entire hand away in order to use it had to be banned. It's so powerful that even a version that requires you to wait three turns before you use it was a major component in a World Championship deck. The only well-balanced Lotus is Gilded Lotus from Mirrodin, later a surprise reprint in Magic 2013. Other than that, Wizards of the Coast has more or less given up balancing Black Lotus (specifically, in keeping the original three mana for low cost, and then sacrifice) which is entirely reasonable for just how infamously powerful it is.
Lion's Eye Diamond is a particularly amusing example as it was an attempt to make an unplayable version of Black Lotus. It failed miserably and is restricted in Vintage due to its power. In some decks, throwing away your hand can actually be useful as well. For instance, reanimator decks can get monsters they want to revive into their graveyard in this way, and madness cards and cards with flashback can be played directly. It can also set up cards in your graveyard for dredging, or for being recast using Yawgmoth's Will. It is actually incredibly broken in conjunction with Yawgmoth's Will: it can be used for 3 mana while Yawgmoth's Will is on the stack then, after Yawgmoth's Will resolves, it can be replayed from your graveyard and sacrificed for ANOTHER three mana without having a hand to worry about discarding. In essence, Yawgmoth's Will + Lion's Eye Diamond can give three free mana and an entire playable graveyard to play around with. Even without access to all the utterly broken cards in Vintage, it is still a force to be reckoned with in Legacy, where it shows up not-infrequently in combo decks alongside Infernal Tutor.
Mox Emerald, Mox Jet, Mox Pearl, Mox Ruby, and Mox Sapphire. These are just like basic lands, except they're artifacts; this means you can play more than one per turn. Much as with the Black Lotus, the benefits to early mana development make these powerful in nearly every deck of the appropriate colours.
Sol Ring, sometimes called the tenth member of the power nine, is another card from the days before they learned the folly of providing cheap cards that provided more mana than they actually cost, especially repeatable ones. Banned in every format but vintage, and restricted there, it is hideously powerful, especially in artifact-centric decks. It actually is an even bigger boost to mana than the moxen, and the only reason it isn't played more is because so many spells in Vintage cost almost no mana. In the decks which can use it effectively, though, it is hideously broken, doubly so if Voltaic Key, a common combo piece, is out as well, as it allows Voltaic Key to double as a second Sol Ring (of sorts).
Mana Crypt, Mana Vault, and Grim Monolith are other examples of fast artifact mana which produce more mana than they cost, and Mana Crypt is as reusable as Sol Ring and gives an even larger initial boost. Mana Crypt and Mana Vault remain restricted in Vintage, though Grim Monolith is not. All of them are broken with Voltaic Key.
Chrome Mox and Mox Diamond have kept up the family tradition by being restricted in Vintage, though this has since been reversed, largely because the card disadvantage is significant, and in the case of Mox Diamond, the fact that you have to give up a land for it makes it much less degenerate in the sorts of decks that love to run tons of artifact mana instead of actual lands (namely, essentially every Vintage deck).
The Mox jewels and Black Lotus' infamy was honored and spoofed with the tournament-illegal Unhinged set's Mox Lotus.
Magic Online parodied both the moxen and the Unhinged card Gleemax by giving us the promo card Gleemox◊, basically all 5 moxen in 1 card.
A powerful (though far more balanced) tribute to the Mox jewels came in the Scars of Mirrodin set, in the form of the Mox Opal.
Timetwister may not seem very powerful, since it's symmetrical, but if it's the last card in your hand and your opponent's hand is full...you see where this is going. It's also the first card that conspired to make Lion's Eye Diamond useful.
Temporal Cascade, a card that can achieve the same effect as Timetwister, was released ten years later, and costs three times as much to get the same effect.
Much later, Time Reversal, cheaper than Temporal Cascade but more expensive than Time Twister, was printed, at a cost that's actually fairly reasonable. What makes the effect of these cards powerful is that you get 7 new cards- but so does your opponent, so it's not nearly as broken if you can't immediately take advantage of your new hand. It actually makes it kind of hard to find a perfect cost for the effect- too cheap, and you can overwhelm your opponent with your new cards before they get the chance to use theirs, but too expensive, and you won't be able to use any of your cards because you already spent so much mana.
Of the other boons, both Dark Ritual and Lightning Bolt have also been phased out, though the latter was given a comeback in 2010. Healing Salve has also been quietly left by the side of the road for being, in comparison, pretty lame. Only Giant Growth endured, being re-printed continuously except for the 2012 Core Set (where it was a potential Game Breaker combined with Scars of Mirrodin's Infect mechanic). Long story short: early editions of M:tG were just riddled with balance issues.
Brainstorm was supposed to be a "fixed" version of Ancestral Recall. It was hideously powerful and eventually got itself restricted in Vintage due to its sheer power; it doesn't help that it combos very well with saclands, which shuffle your deck (and thus shuffle away the cards you put back on top - this allowed it to effectively give card advantage by trading useless cards for useful ones, then shuffling them back into your deck).
Preordain is "fixed" Brainstorm which managed to get itself banned from multiple formats for being too good at digging through your deck, even though it can't give card advantage. Interestingly it sees more action than Serum Visions, which has you Scry 2 after drawing a card.
Another "fixed" Brainstorm, Ponder, also managed to get itself banned from multiple formats. In one sense, it's weaker than Brainstorm in that it will only let you rearrange the top three cards of your library and draw one, whereas Brainstorm would let you take two or three of them and put two cards in your hand back on top of your library, but that's not always that big of a disadvantage, and Ponder also lets you shuffle your library if you don't like what the top three cards of it are.
The irony of all of these "fixed" Ancestral Recall is highlighted in Modern format where all of them have been banned except for the most gimped version, Serum Visions. Even so, it manages to be one of the most popular cards of the format and goes into a wide variety of decks.
In the Time Spiral set, the "Suspend" mechanic was used to create a cycle of new versions of extremely powerful cards in each color, each of which could only be cast by suspending them (normally, at least- they could also be cast by some other methods, such as Fist of Suns or the "Cascade" ability). The Time Spiral version of Ancestral Recall, Ancestral Vision, is basically the same as Ancestral Recall but makes you wait 4 turns to get your cards. And it's still banned in Modern.
Time Walk is the cheapest way to take an extra turn; at one point, every "take an extra turn" card was banned at tournament level due to the huge number of degenerate card combos involving multiple or infinite turns.
One of many, many combos with Time Walk was to put it at the bottom of your library with Soldevi Digger and then use Demonic Consultation to dig it back up. This cost your entire library, so required you to have everything in play you wanted in play, but by using the Digger each time Time Walk was cast you got to draw it at the start of the new turn, cast it for another turn, then use the Digger again...
An interesting story behind Time Walk: It was even more broken before it was actually printed. The text originally stated "Opponent loses next turn." Play testers interpreted this as literally losing the next turn, and it was changed before release.
But there are far more. Bear in mind notes regarding bans and restrictions; Wizards have taken a far more liberal stance on these, and many cards that were once restricted or even banned entirely have had their rulings relaxed from their previous status. In addition, most card errata that radically change a card's function (eg those formerly in place for Great Whale and Time Vault) have been removed in favour of simply clarifying the rules actually on the card.
Also note that many of the following cards may no longer be broken, or never have been broken, simply powerful.
Probably the earliest broken combo in Magic was the combination of Channel and Fireball/Disintegrate, which allowed a first-turn kill to anyone who could get hold of one mana more than it took to cast the two spells. Legend has it an early tournament caused the modern limit of four non-land cards; both players had 20 copies of Channel, 20 copies of Fireball, and 20 copies of Black Lotus, with the match being eventually decided by one player failing to kill his opponent on the first turn. Channel was banned for a very long time, until it became clear the game had changed so much that paying 19 life to power a single easily-countered Sorcery was tantamount to suicide; as a testament to its ability to be used for other terrible things, it remains restricted to one copy per deck even in formats where it's legal.
This one was so well-known it was featured in a comic in the official magazine The Duelist.
Perhaps the most powerful card-drawing card ever printed is Contract From Below. This references an old mechanic called "ante" where players set aside cards at the start of the game and the winner took them at the end, which was axed after falling foul of anti-gambling laws in some US states. The Contract is a ridiculous card; sure, you ante up an additional card and discard your hand (the latter of which could be beneficial in the right deck), but you get 7 cards for only one mana. Like all ante cards, it's illegal in all formats; even if this wasn't so, it's staggeringly overpowered and would likely still be banned.
Sometimes a card does not have to be overly powerful to get banned; it just has to lengthen and complicate the game enough to make it virtually unplayable. Enter Shahrazad, which makes players play a game within a game, with the losers of the subgame losing half of their life points, rounded up. Running four of these meant potentially playing a game within a game within a game within a game within a game, which would make almost any match end in a 0-0 draw.
On a similar note, there's Chaos Orb and Falling Star, which as part of their effects are flipped over from above the playing field and then do something to anything they land on: Chaos Orb destroys any permanent it touches, and Falling Star deals damage to and taps creatures that it touches. What that did to complicate the game was that it made players space all of their cards as far apart as possible, to ensure that those cards couldn't affect too many of their cards, which tended to make actually playing the game a lot more difficult as it was more difficult to see what players actually controlled. It also led to arguments and time-wasting rulings by judges about such things as what exactly constituted a flip, how far it had to be above the table, whether it was actually touching something, and when cards could be moved around. As a result, they both ended up being banned in all formats, making Chaos Orb, Falling Star, and Shahrazad the only 3 cards that aren't ante cards, promo cards, or un-set cards that are banned in all formats. Every other card in the game is playable in at least Vintage, even if that card is on Vintage's Restricted List.
One infamous combo deck was called "Prosbloom," after the two cards that comprised it, Prosperity and Cadaverous Bloom. Rather than relying on creature combat, this deck was based around the "engine" created by these two cards; cards were discarded for mana from Cadaverous Bloom, which then fuelled a Prosperity; this pulled in more cards for the Bloom, with the eventual goal of creating a mega Drain Life for the killing blow. This totally altered the way the game was played.
Cadaverous Bloom also combos with Oath of Lim-Dûl in an earlier version of the various cycling exploits possible with Fluctuator. Don't like a card? Who cares, sling it out with the Bloom then pay the Oath to draw another.
Time Vault has been broken so many times and in so many ways that at one point the Gatherer text used to be a total rewrite of the card which made the ability put a counter on Time Vault which could only be removed by skipping a turn, so that untapping it didn't allow it to be used. The classic method of cheating around the "skip a turn to get a turn" mechanic was Twiddle, but the really evil combo was Animate Artifact / Instill Energy. This allowed Time Vault to be used again each time it created a turn and so made it so the other player could never take a turn at all, and this combo made it the first non-ante card to be banned at tournament level. These days you can do that with a single card, Voltaic Key.
Another combo was with the otherwise harmless-looking Flame Fusillade. Since at one point Time Vault's errata text allowed it to untap at any time, you could untap it as many times as you wanted, skipping future turns- but in between each untap, tapping it to deal one damage, giving you an easy infinite damage combo. It has since been errata'd to only allow you to untap it at the beginning of a turn, and you immediately skip your turn in that case.
Another early combo was based around the long-forgotten Kird Ape, and actually got three of the four cards in it banned or restricted for a very long time. The idea was to cast a Kird Ape with a forest in play (for a 2/3 creature), then give it Giant Growth for a 5/6, then use Berserk to make it 10/6, then Fork the Berserk to get a 20/6 game-winner for just 4 mana. Kird Ape was restricted in Legacy for a while, while Fork and Berserk were both on Vintage's restricted list. This was actually much less impressive than it sounded - while it cost very little mana, it required four (specific) cards, and none of them (apart from Kird Ape) are all that impressive on their own. The fact that the entire thing can be shut down by a single Terror or Swords to Plowshares (or Fog) doesn't help either.
"Tutor" is a name for a series of cards, but also a more general name for any card which has the ability to draw a specific card from your library. The ability is often gamebreaking, since there are some very powerful cards you can go looking for. The original, and possibly most powerful, is Demonic Tutor.
Vampiric Tutor, which appeared in Visions, is arguably more broken. While it causes you to lose two life and puts the card on the top of your deck rather than directly in your hand, it also costs only one mana to cast and comes at instant speed. And like Demonic Tutor, it's spent some time on the banned/restricted list.
Even Demonic Tutor's terrible offspring Grim Tutor can be found enabling degenerate combo decks in Legacy and Vintage. Seeing as it's really the best option that isn't banned or restricted, it's really a player's only choice if they just gotta do something broken.
In Legacy Infernal Tutor and Lion's Eye Diamond do a reasonable impression of Demonic Tutor and Black Lotus in combo decks. Unsurprisingly, they (especially Lion's Eye Diamond) tend to be the poster children of degenerate combo in Legacy.
Balance. In theory, this card balances out the playing field. In practice, it's Armageddon, Wrath of God and Mind Twist, all in one card. The trick to it is to ensure you have Artifact mana and damage sources (with the classic being multiple copies of The Rack), while your opponent does not; they're suddenly left with one card in hand and one land to cast it with. During "Necro-Summer," it was noted to be one of the only cards that the Necropotence decks had any trouble with, since with Balance they'd suddenly find their discard and land destruction had been playing right into their opponent's hands, while they had to throw away all the cards they'd paid for, leaving them with only painfully low life to show for it. A later ally to Balance decks was Zuran Orb, allowing the White player a clean way to throw away all his lands for profit before slapping Balance on the table.
The secret to Balance's power is simple: it controls the number of lands, creatures, and cards in hand, but has no effect on the number of artifacts or enchantments, so while it may clear the field of creatures, reduce the number of lands, and cause an opponent to lose their hand, if you have a large number of artifacts on the field that can deal damage, you win, since by the time your opponent can recover (barring an insanely lucky draw), it's game over. And all for two mana.
The "Bestow" creatures from Theros might finally be an answer to Balance, as they can essentially be "hidden" as enchantments that turn into creatures once whatever-they're-enchanting bites the dust. However, this is of limited utility, since Balance itself sees so little play. You also need a bit of precognition to see your opponent's Balance coming.
And, since it's been mentioned, Mind Twist itself. An obscenely undercosted discard spell, it was so loathed that it won a player poll of cards to be excluded from Fifth Edition by a substantial margin. It proved particularly unpleasant when pulled out early in the game using Dark Rituals and combined with one or more copies of The Rack. It was the third card to be banned outright in all tournaments for being overpowered (Time Vault and Channel being the first two), and the first to be banned entirely for what it could do by itself, rather than any combos including the card. Nowadays it is unrestricted in Vintage and is banned in Legacy. It occupies a rather strange place in terms of power level - in Vintage, there are better things to do with Dark Ritual than getting rid of three cards from your opponent's hand, but in legacy, an early game mind twist off of fast mana can completely ruin many decks. Hymn to Tourach is a slightly less unfair version - while it is still deeply unfair at two mana and can easily mana screw an opponent by making them discard two mana sources, it is not nearly as devastating in conjunction with fast mana, and can't wipe out their entire hand out of nowhere later on.
Fastbond. Remember why Moxen are good? This lets you play as many Lands as you can draw. Everything is now a Mox, all for one mana and a paltry single point of damage each. The combo that got Fastbond banned was with Storm Cauldron, which essentially turned Fastbond into Channel for coloured mana.
Not to mention its interaction with Gush, letting the Gushbond player generate mana and draw cards at the small cost of 2 life. Gush itself is a ridiculously broken card. It's been on and off the restricted list in Vintage multiple times (it's currently legal and unsurprisingly Gush based blue decks are Tier 1) and it's been banned in Legacy since the banned lists were split. Fastbond isn't even legal in Legacy; Gush is banned purely on its own merits.
Another incredibly stupid thing it allows for is the reuse of saclands like Wasteland and Strip Mine in conjunction with Crucible of Worlds, turning it into a one-sided Armageddon.
Alternatively, Fastbond + Crucible of Worlds + Zuran Orb is a game-winner: Play a land, tap it for mana, sacrifice it to the Orb for 2 life, play it from the graveyard with Crucible, lose only 1 life to Fastbond. Repeat as needed.
There are other silly combos as well, such as playing Glacial Chasm which reduces all damage to zero (meaning you can play infinite lands per turn for free, which can lead to all sorts of shenanigans). This is mostly irrelevant though, simply because the only format in which it is legal to do (Vintage), there are too many decks which can kill you in other ways or get rid of the Glacial Chasm and kill you in a single turn before you can replay it, and playing that many lands makes you overly dependent on Fastbond.
This is also banned in Commander. Why? Remember the Zendikar Block, and ALL of the cards with landfall. Fastbond easily triggers the landfall ability coupled with the fetchlands. And then the drawback is totally lost when the player has Grazing Gladehart, because as a result, you gain 1 life instead of having damage being dealt to you.
Additionally, Fastbond is a crazy overpowered card but has two main drawbacks: first, it makes you lose life faster and may end up dead if you don't draw a big card to take advantage of all the insane mana. In Commander, you have 40 life and always start with a castable Commander. Meaning, opening with Fastbond in Commander equals you win.
High Tide is a one-sided blue Mana Flare for just one mana. It's often combined with untapping effects to generate obscene amounts of mana. The classic is Palinchron; with the Islands now tapping for 14 blue mana instead of 7, it's easy to bounce the Palinchron in and out of play as many times as you want to, netting 3 blue Mana each time. Mike Flores described the original Extended High Tide deck as "the most hated deck in the history of tournament Magic, the poster child for Combo Winter."
After dominating Extended for a while High Tide decided it wanted to become the best combo deck in another format so it showed up in Legacy as Solidarity, a deck that ran on the same concepts but played only instants. Solidarity's time came and went and High Tide never really caught on in Vintage so Wizards give Legacy High Tide its most powerful weapon: Time Spiral. After a brief period of panic Mental Misstep stepped in and neutered it again. Then Misstep got banned and it was able to return. Candlebra of Tawnos (X, Tap: Untap X target lands) also comboes beautifully with High Tide.
Duallands, whichhavealmostnodisadvantagesaveforlandwalk. Wow, color doesn't exist anymore. Thankfully, more modern lands that can produce more than one type of mana have some drawback on them to balance them out (for most of them, they come into play tapped unless certain conditions are met, such as requiring another type of basic land under your control or forcing you to pay 2 life).
Another classic unbalanced land is Strip Mine, which is restricted in Vintage and banned almost everywhere else. Land destruction should be a little harder to come by than having a mana-producing non-Legendary Land on the table.
Black Vise was one of the earliest restricted cards; back in early Magic before the proliferation of one- and two-mana drops, if one of these came out on the first turn you'd consider yourself lucky to get away with six damage; with multiple Black Vises in play, you could easily be almost out of the game before it had really even started. Players would often have four on board just to give them a quick cast to get out from under an opponent's Vise. Restricting it, however, allowed other broken cards it had been keeping in check to come out. The game has somewhat passed it by, though, at least in Vintage; despite being unrestricted, it doesn't see much play anymore, mostly because Vintage decks are too fast and too good at emptying their hands. It remains banned in Legacy.
One such card was its opposite, Ivory Tower. This became a staple of Necropotence decks, granting them life to draw more cards from the cards they'd paid life to draw. While it was at one point restricted in Vintage, as the game sped up the card became very weak, and now is unplayable in all formats in which it is legal. It was particularly potent in conjunction with Library of Alexandria.
Necropotence itself. From the moment it was printed, it was everywhere, leading to a period nicknamed "Necro-Summer" where almost every deck in tournament play was a Necrodeck or a deck specifically designed to beat "The Skull." It didn't help at all that under the old rules a player didn't die until the end of the phase even if their life dropped below zero, meaning Necro players could literally kill themselves digging up Drain Life and still finish with a positive life total, or simply use Mirror Universe to give their life total to their opponent. Attempts to depower the deck included bans of Dark Ritual and Drain Life, along with restricting popular Life sources Zuran Orb and Ivory Tower. Ultimately, the card itself was banned; since then it's been unbanned, perhaps most infamously being used to power Yawgmoth's Will / Dark Ritual decks during Combo Winter. A mighty card-drawing engine, Necropotence continues to turn up when a deck is designed around digging up the pieces of a combo quickly, and is still restricted to one copy per deck in tournaments.
Necro also powered the earlier versions of the Trix deck, which was based on using Donate to give an opponent Illusions of Grandeur, something combo players had been searching for a way to do more or less since Illusions came out.
Necropotence later got an upgrade in the form of Yawgmoth's Bargain. Whereas Necro made you wait until your end step to get your cards, Bargain gave you the card instantly. Also, that pesky "exile anything you discard" line was gone too.
Necro-Impotence, the silver-bordered Unhinged parody of Necro, gives you double the cards for the same amount of life, only it also imposes a lock on your own permanents against untapping. While not tournament legal due to its silver border, it is definitely twice as powerful as the original.
It's sometimes said the only reason turbo-mana instant Dark Ritual seemed fair was because it's always been around; it's powered numerous superfast combo decks over the years, and was once banned during the attempts to cripple Necropotence decks.
Dark Rit was also thematically inappropriate; as the Color Pie was re-defined, the decision was made to limit fast mana generation to Red.
White had its own turn at being broken, with the combination of Winter Orb, Icy Manipulator and Armageddon allowing them to shut down the entire game and win by default when their opponent ran out of cards. Such "prison decks" lost some degree of potency when the rules for Artifacts were changed (under the old rules, an Artifact's effect was "turned off" when it was tapped, meaning Winter Orb only affected the owner when they wanted it to), and largely disappeared with the advent of fast combo decks that won long before the board could be locked down, being replaced by much quicker "control" decks. Rising Waters is a more modern variant of Winter Orb.
Zuran Orb is an extremely powerful card for any deck which needs life more than it needs Lands; Balance decks and Necrodecks love it equally, and it's especially powerful when combined with Fastbond.
The Rath and Urza cycles had a huge number of these. The Urza Block has the distinction of having had more cards from it banned in tournaments than any other. It was said at the time that the game had three phases: draw 7 cards, look at your cards, win the game. There's a reason it was called "Combo Winter." It should also be noted that Urza's Saga was the only set to get the entire design team for the set called up to the head office and yelled at.
Memory Jar was unique in being banned before it became tournament-legal; though it's an enormously depowered version of Contract From Below, drawing a new hand is still far, far too powerful an ability to have floating around in an environment full of other power cards.
What makes Memory Jar broken is that it's an artifact so it can be cast off be Mishra's Workshop, played in any deck and most importantly Tinkered for (just in case you couldn't draw any of your other3 manadraw sevens). Time Reversal has the same casting cost as Memory Jar but is utter trash simply because it is not an artifact, though it also has the disadvantage that if you don't win that turn, your opponent gets to keep their new hand of seven cards. It also isn't quite as abusable in some other respects, such as not being able to be recast under Yawgmoth's Will quite as easily.
The above-mentioned Yawgmoth's Will is one of the most powerful cards ever printed: just get a lot of cards into your graveyard (something Black is good at), especially multiple copies of Dark Ritual, then drop the Will and you suddenly have obscene card advantage, usually enough to win the game outright. Restricting it, uniquely, doesn't really help, since it's rare a player will want to draw it early on before they've had a chance to fill up their graveyard. A particularly nasty Vintage deck called Long.Dec (scroll down) used Burning Wish to abuse a sideboarded copy; with a 60% first-turn kill rate, it was one of the most powerful decks in the format's history and duly got Burning Wish (and Lion's Eye Diamond, a card once thought completely useless) a place on the Restricted list alongside Yawgmoth's Will itself.
Yawgie got another broken card to his name, in the form of Yawgmoth's Bargain. This is turbo Necropotence, skipping that whole annoying part where you have to actually wait to get the cards. On the one hand, it's expensive. On the other hand, it's in the same block as Skirge Familiar. This did not end well; in fact, the Bargain was banned in the Extended format before it had even rotated into it.
There's a common joke that Yawgmoth's Bargain is "I'll take your common, useless Healing Salve and give you an out-of-print, rare, Vintage-restricted, game-breaking Ancestral Recall." Far worse was that the Ineffable comboed with "spellshaper" cards in the next block, meaning you essentially had "Pay 1 life: Do whatever the hell you want."
Mark Rosewater has referenced Yawgmoth's Bargain a couple times when talking about mistakes he made in card design and this taught him that that anything that will exchange 1 card for 1 life and is reasonably costed is going to be broken. Interestingly, in another article he implied that they justified the card by reasoning that 6 mana was too expensive for it to be broken (in all fairness, six mana is a lot).
One of the best lands ever printed, Tolarian Academy. It's known for being the centerpiece to dozens of broken decks and infinite mana combos, including:
The Tolarian Academy / Candelabra of Tawnos / Capsize combo. This is a little harder to see since the main rule isn't actually on Candelabra of Tawnos. Old Artifacts were always assumed to tap to use their abilities. With at least nine Artifacts in play, you tap the Academy for nine blue mana, use the Candelabra to untap the Academy (cost 1), then use Capsize (with Buyback, cost 6) to return the Candelabra to your hand, casting it again afterwards (cost 1). The board is now back to how it was, except you have one blue mana. Repeat until you have more mana than you know what to do with.
Somewhat similar to Tolarian Academy, Gaea's Cradle. Now, remember there are lands that are creatures, mana source creatures, cards that make lots of token creatures, and Living Lands. So, this can work out as a zero-cost, one-way Mana Flare which also turns every creature into a Forest you don't need to tap.
Grim Monolith itself is also broken when combined with Power Artifact, allowing it to untap for one less mana than is generated by tapping it.
Dream Halls is a powerful card which allows any coloured card to be played by simply discarding another. It was at it's most powerful when played with 'free' creatures like Great Whale; you could throw down a Great Whale and untap all your Lands, even though you hadn't actually tapped any lands to pay for it. Errata were issued quickly saying that such creatures could only untap lands if they came into play from your hand, though these have since been removed.
Tinker. Combined tutoring with automatic casting, all for three mana and sacrificing an artifact. Since artifacts exist that cost nothing, as long as it was around it was impossible to balance any artifact with a high casting cost; all artifacts could be cast for three mana. Resulted in the so-called Pro Tour Tinker in 2003, where seven of the top eight decks had four copies of the spell.
The card's original (pre-October 2004) wording had the player sacrifice an artifact as Tinker was cast. Since that wasn't considered an additional cost to the spell, a player with no artifacts to sacrifice could still cast Tinker.
Not to mention that Mirrodin Besieged "blessed" us with Blightsteel Colossus so now blue mages can win in one swing instead of two or, God forbid, three like the old, crappyrobots of yore.
Recurring Nightmare, a repeatable way to put creatures from your graveyard into play, thanks to having zero-cost automatic buyback. Combos with, among others things, Great Whale; endlessly Recurring a pair of Great Whales (one in the graveyard and one in play, constantly swapping which is which) creates an infinite mana loop. The killing blow from this deck was to shift Recurring Nightmare to a graveyarded Triskelion, which was then Recurred until it had shot the other player to death; if you have it deal the last hit to itself, Triskelion has the advantage of killing itself, allowing it to return anew.
Survival of the Fittest is a reusable, super cheap tutor which practically makes it broken by default. Once upon a time Vintage players feared a deck called German Tools 'N Tubbies or simply TNT that used Survival alongside Mishra's Workshop to do lots of broken things. The deck would get Anger, Genesis, and Squee, Goblin Nabob into its graveyard in order to tutor up a hasty Goblin Welder who would procede to cheat Juggernauts into play (they were the Tubbies; Juggernauts were credible threats back in the day, surprisingly). Also, it played singleton creatures who did something specialized to help them swing matchups that otherwise might be not so hot.
Oath of Druids is another "balancing" card, and another one that turned out to be hideously broken if a deck was built around it. Continuing the Balance tradition of being ridiculously cheap, it ruled tournaments in various forms for a long time prior to being variously banned and restricted; an Oath deck simply plays control while it digs up the Oath, then goes off almost instantly. A classic combination was for players to use Forbidden Orchard to give their opponent creatures, allowing them to bust out huge creatures from their own deck as early as turn 2. These days it's potentially even more powerful, since the Oath works out as paying 2 mana for huge creatures like Emrakul, the Aeons Torn.
Oath also continues the proud tradition of Ancestral Recall: namely, ridiculous power disparity within cycles. Oath of Druids was part of a cycle of Enchantments in Exodus that provided a each player a benefit during their upkeep provided they have less of a specific resource than their opponent. The rest range from unplayable trash to I might have seen it in Block Constructed. Here's the rest of the cycle: Oath of Ghouls (black), Oath of Lieges (white), Oath of Mages (red) and Oath of Scholars (blue).
Cursed Scroll looks like a bluffing card, until you start emptying your hand before using it. When your opponent can only choose the one card you drew that turn, it works out as a colourless Shock. For a while, you could reasonably expect to see four of these in every top-level deck which didn't like holding cards.
Lotus Petal does exactly one third of what Black Lotus does, and still proved too powerful. Zvi Mowshowitz once defined a broken combo deck as one that would use Lotus Petal if it could.
And Stronghold got in on the act with a Mox, Mox Diamond. While not as powerful as its brothers in the Power Nine, it's still spent time on the restricted list.
Intuition is much like Kamigawa's Gifts Ungiven, save that you only get one card; however, it has the huge advantage that you can search for three copies of the same card with it and give your opponent no choice at all as to what you end up getting. It's also powerful in reanimation decks, since it can be used to make your opponent put big creatures into your graveyard.
Hermit Druid was killed off by bannings almost as soon as decks using it appeared; the general idea of "Angry Druid" decks was to have few or no basic lands, allowing the Druid to dump the entire library, filled with powerful creatures, into the graveyard. A reanimation spell would then be pulled back into the library with Krosan Reclaimation and used to pull Sutured Ghoul from the graveyard (usually picking up Dragon Breath along the way); the resulting trampling mega-Ghoul, typically powered by multiple Krosan Cloudscrapers, would generally easily win the game.
Masticore, an efficient creature that regenerates and most importantly gives your deck the ability to burn down creatures no matter what color you're playing.
In its heyday, it was played heavily in blue control decks as a finisher. At the time, blue control was referred to as "Draw-Go" because that's how its turns went - "I draw. Go." It had a ton of cards laying around to pitch to Masticore once it hit the table. And it could easily burn out a lot of the creatures that blue let through to the table early on in the game. When blue is doing most of the burning in your format, something's gone horribly wrong.
Windfall, similar to Timetwister in its ability to refill your hand while giving your opponent nothing.
Fluctuator. Cycling is a mechanic which allows you to discard a card in your hand to draw a new one, by paying the cycling cost. All cycling costs at the time were the same as the amount this card reduces them by. In other words, if you don't like your hand, just throw out cards and draw more until you do, all for nothing.
Time Spiral was broken for pretty much the same reasons as the original Timetwister. Of course, it's more expensive. But came out in the same format as Tolarian Academy. Oh, and because Tolarian Academy can be among the lands you untap, you can quite easily gain mana by casting it.
Mind Over Matter, one of the most versatile combo enablers in magic. Among many many others, see Tolarian Academy. Again.
Sapphire Medallion. Because blue has such problems getting hold of mana in the Urza Block they needed a special card to make all their spells cheaper. Presumably the card letting you set your opponent's deck on fire wasn't powerful enough.
Metalworker, a hideously undercosted creature that dovetailed right into the "have loads of artifacts" Tolarian Academy decks to give them even more fast mana. These days it can produce infinite mana when combined with Voltaic Construct; all you need to do is have more then one Artifact in your hand.
Pemmin's Aura can give any creature all of Morphling's abilities, for only 3 mana! You can even stick it on one of your opponent's creatures and use it's +1/-1 effect to kill it!
If it's just big creatures you want, then Tinker for a Phyrexian Processor. The ability to put Minions into play for 4 mana no matter how big they are is powerful in itself, nevermind all the ways to make it activate more cheaply or use it multiple times in a single turn.
Replenish auto-casts every Enchantment in your graveyard for 4 mana. Bear in mind that Academy Rector costs the same, only gets one Enchantment into play, and has to die first, and is regarded as one of White's best cards. The Replenish deck would sit back loading the Graveyard with Enchantments using Attunement, then throw out expensive, powerful Enchantments like Parallax Wave, Opalescence and Seal of Clensing all at the same time. It was duly banned or restricted in every format.
Humility. There are cards that hose colours, cards that hose types, but only one hoses "creatures that do anything" to this scale. To add to the fun, if you can turn your opponent's lands into creatures they can't tap for mana anymore. Play it with Opalescence in play to make your opponent's head explode as they try in vain to figure out how the two cards interact with each other (just look at the errata on Humility - hey, you just lost D6 SAN and gained ten Cthulhu mythos. Congrats!). Depending on the order of casting, day of the week, phase of the moon, position of the five suns, and whether your human sacrifices have pleased benevolent Yawgmoth, Humility can actually end up removing its own effect and becoming a 4/4 creature.
Stroke of Genius is one of the most powerful card-drawing cards, to the point at one Pro Tour a player in a tournament match resigned after asking to read the card text. It was typically the killing card of any Urza-block blue deck; making the other player draw 54 cards being auto-lose. This was often preceded by the player using it to dig out most of their own library, a procedure perhaps inevitably called "stroking yourself."
Worldgorger Dragon ended up banned in several formats due to the way it interacted with enchantments like Necromancy, Animate Dead and Dance of the Dead. The general idea was to get the Dragon into a graveyard, then get it back into play with one of these enchantments; the Dragon would remove the Enchantment that bought it to life from the game as it came into play, killing itself and bringing back all your other permanents...untapped. Along with them, the enchantment would return, ready to target the Dragon again, and in response you tap the lands for mana. This could be repeated indefinitely, and would result in a draw unless it could be interrupted somehow. The simplest win condition for such decks was to channel the mana into a massive instant-speed spell like Ghitu Fire or Stroke of Genius, but later versions would graveyard a card like Ambassador Laquatus, Shivan Hellkite or Sliver Queen with an infinitely repeatable ability, then have the enchantment target it instead of the Dragon to break the loop. A third version was to use cards with powerful comes-into-play effects which triggered every time the cycle ran; one variant used Eternal Witness to endlessly recycle and use Ancestral Recall on the other player until they ran out of cards.
The interaction between Dragon and Animate Dead is also notorious for being one heck of a rules headache. Even though Dragon is no longer the dominant force it once was (although it still shows up and places from time to time) it's been suggested (although not proven) that it remains of the Legacy banned list because of the rules problems it creates. The combo has been called a "rules glitch" and when it was commonly played judges noted that they got inordinate amounts of rules questions regarding interactions with the combo. In addition, players tend to dislike playing against the deck because without a Bazaar of Baghdad in play or a win condition in hand or the graveyard casting a reanimate enchantment on Dragon ends the game in a draw because there is no way to break the loop. This is a common tactic employed by Dragon players in the face of defeat (Necromany even let them do at instant speed so they could respond to lethal damage by forcing a draw) and so it was not too uncommon to see matches with Dragon decks go to 4, 5 or more rounds.
Mind's Desire was restricted in Vintage and banned in Legacy before it was even tournament-legal. It was one of only two cards to get such a preemptive ban, the other being Memory Jar, owing to the number of disgustingly powerful things that can be done with as many free spells as you've played spells this turn; the typical play was to use Mind's Desire to build up the storm count further for a lethal Tendrils of Agony. This was the metagame in Standard when it came out.
4UU might seem like a prohibitively high cost, especially since Mind's Desire must be played after many other spells to become a Game Breaker (Yawgmoth's Bargain is the only other 6 converted mana cost card that gets used without being cheated into play), but with spells thatcost nothing available, this problem is easily worked around.
Counterspells, normally the bane of combo decks, can't do much to stop Mind's Desire, since countering the original does nothing to counter the copies created with Storm. Stifle was released in the same set as Mind's Desire; it probably would have been an unused niche card if not for its ability to counter Storm.
Mark Rosewater has said that Storm is extremely overpowered and may be the most broken ability or mechanic in the entire game, including everything from the Rath, Urza and Mirrodin blocks. His tumblr account, Blogatog, frequently references the "Storm Scale", rating how likely a mechanic is to ever return to Standard, with 1 being "pretty much guaranteed" and 10 being "no way in hell we would ever risk it"; it is named this because Storm is located at 10.
Tendrils was also a game breaker on its own-a deck could use tutors, draw spells, or Yawgmoth's Bargain, plus any of the above-mentioned free cards, to get a large enough Storm count to kill an opponent in one shot.
There's also the Mirrodin block, a very Artifact-heavy block with the ability to even have Artifact lands, the only cards that traditionally couldn't be Artifacts. So, your entire deck can consist of Artifacts (though this required some thought as the artifact lands were limited by the 4 of a kind rule). Setting aside the Affinity mechanic (cards that get cheaper the more of a certain type of card you have, and why yes there were cards with 'Affinity for Artifacts'), let's throw in Arcbound Ravager that gets tougher every time you get rid of an Artifact. Hell, while we're at it let's throw in Disciple of the Vault who deals a point of hard-to-redirect life loss (not damage) to your opponent every time Arcbound Ravager gets tougher. Now, let's remember you can have up to four Disciples in play at once; this means the 55 cards in your deck that aren't Disciples or the Ravager can kill your opponent eleven times over and give you a 56/56 creature, and if that somehow dies it allows you to make any other artifact creature in play a 57/57 creaturenote Yes, we know you already sacrificed that creature to the Ravager to make it 56/56, it's just for the example and your opponent loses four life just for doing that. As if that wasn't enough, you could also give the Ravager Cranial Plating so that any Artifacts you hadn't sacrificed to it (including the Cranial Plating and the Ravager itself) also made it tougher. The Artifact Lands, Arcbound Ravager, and Disciple of the Vault all ended up banned. Another card that rode on the Disciple's power is Shrapnel Blast, which could leverage the lifeloss trigger to make throwing explosive artifacts at your opponent (or their creatures) that much more effective.
Mirrodin also gave Vintage players the extremely nasty Trinisphere, which could slow down the lightning-fast plays Vintage is famous for. Chalice of the Void and Engineered Explosives also see a fair amount of use in Legacy and Vintage as well, due to their flexible and powerful abilities.
Seemingly trying to cement Mirrodin as the next Urza / Rath block in power terms, there was also fast mana in the form of Chrome Mox, which had a visit to the restricted list in Vintage in 2004.
Skullclamp. What's the problem that Zerg Rush decks often face? They run out of cards, and if that's not enough to kill their opponent they lose momentum. So they printed an extremely cheap equipment that lets you strengthen or kill your creatures and draw two cards every time it happens.This article explains that it was banned because it was sucking the entire format into a Skullclamp "black hole."
Æther Vial also saw a trip to the banlist; since it puts cards directly into play without requiring them to be cast, they can't be countered. Free, uncounterable creatures at Instant speed every turn proved irresistible to a great many decks. The Vial could even be used with Power Conduit to manipulate its charge counter stockpile on the quick.
Platinum Angel: You cannot lose, and the opponent cannot win. Incredible for stopping certain kinds of combo decks short. Attach Shield of Kaldra to it, or otherwise prevent your opponent from removing it from play with abilities like Hexproof or Shroud, and you've got the game in the bag.
Krark-clan Ironworks was deliberately designed by R&D to be a combo engine enabler. Paired with little creatures like the Myr Moonvessel and the Myr Retriever, some very degenerate combos can quickly be enabled. Used in conjunction with the aforementioned Artifact Lands, you can quickly build up enough mana to retrieve a finisher like the Goblin Charbelcher, which combos very nicely with the Myr Incubator that can help you purge the artifact lands from your library and give you more Myr Token creatures to feed to the Ironworks for more mana. For a time, Charbelcher actually became a completely disgustingly powerful combo deck archtype in Vintage (where you could run even fewer lands thanks to the 5 Moxen and the Black Lotus and the Lotus Petal), only held in check by spells like Force of Will and artifacts like the Null Rod. Myr Servitors also quickly become easy reusable fuel for the Ironworks in longer games.
Ironworks plus two Myr Retrievers, one in play and one in the graveyard, allows you to sacrifice one Retriever for 2 mana while getting the other Retriever back from the Graveyard, use the mana to play it, sacrifice that Retriever for mana to get the first Retriever again, play it, repeat ad infinitum. It equals an easy Storm counter buildup, and can cause other cards to trigger when the artifacts go to the graveyard or enter play. As an example of the former, toss in the aforementioned Disciple of the Vault to give your opponent a swift death. As an example of the latter, toss in Genesis Chamber to give yourself infinite 1/1 Myr Tokens, which you can use to generate infinite mana, or give your Arcbound Ravager infinite Counters, or mill your opponent to death with Grinding Station, a combo that later received a Shout-Out on an Un-Set card .
Retract quickly got broken in as a powerful Storm counter enabler, being used in conjunction with large numbers of low-cost artifacts to let you cast and then recast multiple spells rapidly for one measly blue mana; it also limits the ability for multiple artifact lands to linger on the battlefield, and easily feeds spells and abilities that could exploit multiple artifacts entering or leaving play. In particular, formats like Legacy and Vintage make this spell into a powerful beast, as it could "untap" all of your Moxen at once (by unsummoning all your tapped moxen and letting you resummon them untapped)!
Sundering Titan was a major force in Tooth and Nail decks, and is absolutely devastating where multiple basic land types are in play, especially in multiplayer matches. The Titan was also a beast in conjunction with spells and abilities that allow it to enter and leave play repeatedly, like Astral Slide, Goblin Welder, Trash For Treasure, reanimation spells, Tinker, or Venser, the Sojourner, and using Kiki-Jiki, Mirror Breaker to create temporary token clones of it was just as devastating. To trample your opponents in the dirt further, his ability is worded such that the Titan allows you to destroy one of each basic land type when it enters or leaves play, so once the summons resolves your opponent is only going to hurt more trying to kill it, and even moreso if they share basic land types with you as you can hit their lands instead of yours. Furthermore, this ability does not target lands so it ignores Hexproof and Shroud.
Speaking of Tooth and Nail, it was the other premier deck archtype of the Mirrodin era, as the power it yields when cast with Entwine makes it disproportionately devastating and appropriate for a hefty 7GG. In its native Green, Tooth players could either dig up powerful, game-ending threats like Darksteel Colossus, the aforementioned Sundering Titan plus Kiki-Jiki, Mirror Breaker, or other flexible creature combinations that feature premier creatures like Eternal Witness, Triskelion and a Mephidross Vampire whose ability allows Triskelion to regenerate its +1/+1 counters as it machine-guns your opponent's creatures, the aforementioned Platinum Angel plus a Leonin Abunas who gives your artifacts (including the Angel herself/itself) Hexproof, or just about anything a sufficiently creative player could pair up for the Tooth to pull straight into battle from your library. As a matter of fact three entire mana engine variants of Tooth decks prevailed, some leveraging Urza's Lands alongside Sylvan Scrying and Reap and Sow, some using Cloudposts, and others using Green's natural mana acceleration and Vernal Bloom to pump vast amounts of green mana out for the big spell.
While the Kamigawa block was otherwise fairly low-powered, it did have Gifts Ungiven. This extremely powerful tutor card essentially made your opponent pick how they were going to die; it's restricted in Vintage and banned in several other formats.
There was also Umezawa's Jitte. Not quite as game-breaking as the likes of Skullclamp, but severely undercosted for its powerful abilities. Some commentors on the Gatherer website treat it as the "First Colourless Planeswalker" (an actual colorless planeswalker, Karn Liberated, was later printed).
Time Stop is a counterspell on crazy steroids. It doesn't just prevent a spell from resolving, even those immune to countermagic, it also wipes the stack and exiles any spells still on it, preventing recursion by graveyard diving players. While fairly costly to cast, it's the ultimate lategame stopper for many a dangerous board situation.
Heartbeat of Spring is a green Mana Flare. Mana Flare always sucked, so they figured that printing it in the right color couldn't hurt anything. Turns out that Mana Flare just hadn't had the right environment. While a seemingly symmetrical effect, instead the card allowed for a very asymmetrical effect as it was only cast on the turn the player would win. A large amount of mana accelleration would be used, Heartbeat of Spring would come out, then a spell that untapped all your lands, followed by transmute cards like Drift of Phantasms, which could be used to tutor not only for Heartbeat of Spring, but also for Early Harvest to untap your lands, and Maga, Traitor to Mortals and similar win conditions that cost three mana base plus X, where X could easily be 20 or more, allowing for an instant kill. It generated a top tier combo deck, and neither Early Harvest nor Heartbeat of Spring have ever been reprinted, very likely as a direct result of its existence.
Sensei's Divining Top's subtle yet powerful draw-manipulation (pay 1 mana to see and rearrange the top 3 cards of your library; tap: draw a card and put the Top on the top of your library) is incredibly powerful in the non-Vintage formats, being an inexpensive draw-fixer that lets you control your future draws, even after deck-shuffling tutoring. Its ability to draw a card also gives it the ability to dodge hatred, as it can draw a card and jump on top of your library to evade targeted destruction. In many cases it effectively lets you extend your "hand" to include the top three cards of your library! Currently the Top is banned in Modern, both because of its disproportionate power/utility to cost ratio and because it simply makes games take too long.
Some Eternal deck archetypes are built on quirky instawin combos; Painter / Grindstone comes to mind as one of the more prolific, mainly due to the satisfaction of milling someone's entire deck in one go. These cards are rarely banned on the grounds that getting the cards out is the real challenge of combo decks.
Another popular instawin combo has been broadly termed "Hulk Flash," which worked by comboing Protean Hulk and Flash to assemble a suite of game-winning creatures. Some variants of the deck could win on the opponent's upkeep of the first turn when going second using Gemstone Caverns and either Simian Spirit Guide or Elvish Spirit Guide to get the mana to cast Flash. There are a lot of sets of creatures that can be gotten with this that will give an insta-win if all come into play simultaneously- 4 Disciple of the Vaults, 4 Phyrexian Marauders, and 4 Shifting Walls, for instance, since the Marauders and Walls come in with no counters and instantly die, each causing all 4 Disciples to go off for a total of 32 points of life loss, all on your opponent's first upkeep.
Dark Depths is one of those cards that combo players study intently to figure out how they can make them go off quickly, and for a long time they couldn't. But sure enough, with Urborg, Tomb of Yawgmoth to make Dark Depths produce mana and Vampire Hexmage to yank the counters off it, it's possible to have a 20/20 creature in play as early as turn 1 (using Fastbond), and turn 2 otherwise.
The Magic 2014 legend rules added a new way to cheat around Dark Depth's enormous cost with Thespian's Stage: When Thespian's Stage becomes a copy of Dark Depths, it will have no ice counters on it and the new legend rules allow you to remove the original Dark Depths while leaving the new one intact.
All cards from the Unglued and UnhingedSelf-Parody sets are banned in normal play, but some of the cards from these sets are so overpowered that if used in normal play they would be considered an enormous game breaker. R&D's Secret Lair (which doesn't so much break the game as destroy it) and Gleemax (which lets you control any card in play if you can sneak around its enormous casting cost) are key examples.
Jace, the Mind Sculptor has the distinction of being the first of the planeswalker card type to be banned, and while still in Standard too, the format which is both the most heavily scrutinized for card interactions and the one in which they are most reluctant to ban cards. In April, one tournament saw every top 8 finisher running the maximum 4 copies of Jace, The Mind Sculptor. There were 32 copies of Jace and 32 copies of Preordain in the top 8 - something almost unheard of in Magic history. At the time of the ban Jace was selling for between $80 and $100, a shocking cost for a card in a set released so soon.
From the same set as Jace, Stoneforge Mystic, a card that allows you to fetch any Equipment, then later put it into play for two mana rather than what it actually costs. It was "merely" good for awhile, but then a card called Sword of Feast and Famine came along to make it awesome, especially in combination with manlands and Squadron Hawk, all of which have evasion, making repeated equips more bearable. Then a card called Batterskull was released in the New Phyrexia set, giving the Stoneforge Mystic an even better equipment to put on the table (essentially casting an uncounterable 4/4 creature with vigilance and lifelink for 2 mana as early as the third turn- or even the second turn, if you were lucky enough to have in your opening hand a Stoneforge Mystic, a Plains, a Mox Opal, and two other zero-cost artifacts, and there were severaldecentones at the time). This was also banned at the same time as Jace, the article explaining why commenting that the two were dominating tournament play to a degree possibly unprecedented in Magic history.
The manual for Fifth Edition even had an entry for "Loop, Continuous" in the index. The entry would refer to three Magic cards hidden in the index that formed an infinite combo.
And it should be noted that that Website is more than a decade out of date, and plenty of new infinite combos have been made possible since then. Though Wizards has generally gotten better about not allowing them (or at least making them harder to pull off), there are still many decks build around exploting them. Some examples of infinite loops:
Myr Galvanizer can, for one colorless mana, untap all other Myrs you control. Some Myrs are capable of producing mana, so if you have 2 Myr Galvanizers and at least 2 of the Mana-ProducingMyrsthatgenerateonemana when tapped (or one Palladium Myr, which generates two colorless mana), then you can tap the Mana Myrs for 2 mana, pay 1 to tap one of the Galvanizers and untap them, tap them for two more Mana, tap the other Myr Galvanizer to untap the Mana Myrs again and the other Myr Galvanizer, and repeat to get as much mana as you want that those artifacts can produce.
Exquisite Blood and Sanguine Bond basically have the opposite effects- Exquisite Blood heals you whenever one of your opponents takes damage, and Sanguine Bond damages your opponents whenever you get healed. Neither is terribly overpowered on their own, but when you have both at the same time, anything that triggers the effect of Exquisite Blood will cause Sanguine Bond's effect to trigger when Exquisite Blood's effect resolves, and vice versa, creating an infinite loop that instantly kills all of your opponents as soon as either you heal so much as one life or any of your opponents takes so much as one damage.
The Shadowmoor Block introduced a number of cards that untap rather than tap as part of an activated ability cost. Sure, all of the abilities cost a bit of mana, and you have to get them tapped to use the ability, but tapping them isn't too difficult, especially if you use a card like Paradise Mantle or Utopia Vow to make the card in question continously tap for mana, effectively cheapening the cost of their ability and letting you repeat it as long as you have enough mana. This limitation was lowered a bit by Heartstone, and basically removed once Training Grounds appeared, which can reduce almost all of the untap cards' ability costs to 1- or 0, if you find a way to tap them for mana, thus allowing such things as infinite 1/1 tokens, infinite mana, or a +infinity power boost to all of your creatures.
The Duskmantle Guildmage and Mindcrank combo. Duskmantle Guildmage makes your opponent lose life every time they mill cards from their deck, while Mindcrank makes them mill cards every time they lose life. For that matter, Duskmantle Guildmage's ability can make them lose life if a card goes to their graveyard from anywhere. Discarded a card? Combo goes off, they lose. Card on their field goes to the graveyard? Combo goes off, they lose. Even casting an instant or sorcery that doesn't destroy Mindcrank causes them to lose when that spell resolves! Mindcrank can also combo with Bloodchief Ascension although that requires you to get three required quest counters on Bloodchief Ascension. On the other hand, Bloodchief costs less, is an enchantment (and thus harder to remove), and once it gets the counters, the ability is always active instead of requiring 3 mana to activate.
They tried again to make a "balanced" Black Lotus with Lotus Vale at the cost of two untapped lands to be sacrificed to the graveyard. Unfortunately, it could originally be tapped in response to having to sacrifice it for not paying the cost. Consequently Oracle had to completely rewrite the wording.
Griselbrand. He's not considered much of a thing in Standard, where eight mana is a pretty tall order (though he does show up in Standard decks from time to time). In Legacy, however, this guy is very powerful, being a Yawgmoth's Bargain attached to a 7/7 flier with lifelink. And once he resolves, the nature of the deck makes him hard to get rid of, as you have to beat not only your opponent's hand, but the top seven in their deck (though sneak and show's other creature, Emrakul is even harder to kill). And with free counterspells like Force of Will commonplace in Legacy, that's difficult even with a counterspell of your own. Some even argue that he be banned for giving sneak and show too much consistency.
Moving out of Sneak and Show, he now enables Tin Fins, a black storm combo deck that can go off turn 1 pretty often and turn 3 at the absolute latest thanks to his synergy with Children of Korlis, burn (upto, some cases may want to be safe with just 7) 14 life to draw 14 cards, play Children of Korlis, regain 14 life, burn that 14 to draw 14 more cards, play a second Children of Korlis and gain 28 life, draw out the rest of your deck and then storm Tendrils of Agony with practically your whole deck in hand.
He was banned in Commander, another game format where players have 40 life instead of 20... making his ability essentially free.
Innistrad managed to bring its own headache in Snapcaster Mage. Combined with ways to flicker it—which were more than a little profuse in Avacyn Restored—counterspells quickly became overly profuse on their own. Return to Ravnica is already filled with ways to contend with him...which are themselves so unnervingly powerful that players are already asking why Snapcaster wasn't just banned. The clincher is that he's not entirely R&D's fault—Pro Tour winners get a prize of designing a card of their own for a future set, and this is one of them.
The entire dredge mechanic was a disaster. The theory behind it was that the cards were a bit worse than normal cards, but you could ensure you drew the same card every turn, and they would help you find other dredge cards in the process. In practice, only one dredge card was actually worth casting - Life From the Loam, while the rest were simply not worth playing because why would you WANT to get a subpar card every turn? Even Grave-Shell Scarab wasn't very good, despite being an effectively unkillable 4/4 creature. So what was the problem?
Arguably Dredge was incredibly under-estimated by R&D and easily the most overpowered guild mechanic in all six Ravnica sets: In a game like magic, being able to draw more cards is a strong ability, Dredge turned out to be overpowered because it made the graveyard function as an extension of the player's hand and shrugged off most forms of disruption. Being Black and Green it was in the colours that have some ability to play spells or creatures from the graveyard or retrieve them from the graveyard into your hand. When choosing to Dredge the weaker dredge cards, the player basically moves a card that can't be played from the graveyard to their hand and then moves a number of cards into the graveyard from their library based on the dredge number. If the cards that were put in the graveyard were capable of being played from the graveyard or easily retrieved, then what functionally happened was that the Dredge player was able to move 1 card into a castable position and then draw X cards where X was the dredge value of the dredging card. Dredge decks basically get to draw more cards per instance of "draw a card" than opponents and then have the sweet broken advantage that any disruption like counterspells, milling or discarding effects result in the cards affected effectively returning to their extended hand, drawing more cards into their extended hand or setting up more dredge effects. They only way to outright interfere with them was to play heavy graveyard hate or have removal/hate cards that exiled the target instead of sending it to the graveyard.
In extended, Life from the Loam could be used to bring back sacrificed fetch lands, the net effect being that you could replay your fetchlands over and over again and thus pull all the lands out of your deck, improving your draws. This wasn't great on its own, but in conjunction with cycling lands - lands you could discard to draw cards - Life from the Loam became a card drawing engine, as you could cast Life from the Loam to grab back a fetchland and a pair of cycling lands, play the fetchland to pull out another land from your deck, then cycle your cycling lands to draw two cards (or potentially dredge back up Life from the Loam, dumping MORE cycling lands into your graveyard for you to fetch...). The deck played cards like Terravore, which became monsterously huge due to the number of lands dumped into the graveyard, Devastating Dreams, which Terravore could survive, Life from the Loam could fuel with a huge hand size, and which would wipe out all the lands and all opposing creatures (but leave your Terravore intact...), and Seismic Assault, which meant Life from the Loam effectively read 1G: deal 6 damage distributed amongst up to three targets. Worst of all, there was little that could be done about it - countering Life from the Loam was a waste of time and the deck could draw scads of cards off of very little mana, and could run a lot of lands, allowing it to be more consistent.
In Vintage, it allowed a deck called Manaless Ichorid to exist. Bazaar of Baghdad combos extremely well with a dredge deck, and if you don't NEED to cast any spells, you can do something insane - such as, say, RUN NO LANDS - and thus run four copies of Bazaar of Baghdad and four copies of Serum Powder so that you can ensure that you ALWAYS get a Bazaar of Baghdad in your opening hand. As the deck runs scads of dredge cards, all you need to do is find one dredge card and you can quickly dump your library into your graveyard. Ichorid doesn't cost mana to get into play in this situation, Narcomoeba comes into play for free as well, Street Wraith lets you dredge cards even faster, Dread Return allows you to bring your Golgari Grave-Troll into play, and Bridge from Below allows you to spew out piles of zombie tokens for free... the net effect is a deck which can win on turn 3 reliably, turn 2 occaisionally, and on a god draw kill you on turn 1. Oftentimes without casting a single spell, thus rendering all countermagic useless. While the deck is only dominant in Vintage if unprepared for (and everyone prepares for it because it sucks losing to a deck that dumb), the deck fundamentally circumvents the basic mechanics of Magic, not requiring mana to function. It doesn't help that Vintage decks are not really equipped to deal with hordes of monsters - Swords to Plowshares and similar spot removal is not especially useful against the deck and won't save you from being swarmed. Thus many decks run four copies of some graveyard hate spell - like Leyline of the Void - in their sideboard and just mulligan until they get it in games 2 and 3.
From the Commander 2013 set, we were given True-Name Nemesis, lovingly nicknamed Progenifish due to being able to No Sell a player entirely. In the multiplayer style of Commander/EDH, he's not a big of a deal and encourages table politics and alliances. However, he's legal in Legacy and Vintage, where once he's on the battlefield he's pretty much there to stay barring someone being forced to sacrifice him or a board wipe. Due to his ability, just him alone will force the opponent to lose in 7 turns (the damage he does cannot be stopped at all, so he only needs to attack 7 times), however he also happens to be a blue merfolk; one of the most powerful tribal decks in Legacy (which happens to have 8 "lords" that can pump his strength and a slew of counterspells to avoid other shenanigans, meaning that more realistically the opponent only has about 3 turns to do something about him). He's the reason the Grixis Commander 2013 deck goes for almost triple the price of the others at most stores.