History GameBreaker / LeagueOfLegends

** Eclipse started off exceptionally strong, giving assassins a powerful percent-health damage as well as safety on a relatively modest cooldown that was just way too powerful for its own good. Combined with the bonus armor penetration from its mythic passive, as well as [[LifeDrain omnivamp]] as an icing at the top of the cake, it became a must-buy for not just assassins, but even some bruisers and marksmen too (like Pantheon, Jhin and Graves) due to its utility being so useful. It was eventually brought more in line by lowering the percent-health damage and movement speed bonuses, as well as halving the effectiveness on ranged champions [[ObviousRulePatch to make them buy the weapons actually intended for them.]]
** Both of the Ironspike Whip-based Mythic items turned out to be incredibly wild on juggernauts:
*** Goredrinker first gained traction as the more powerful of the two as its ability to let juggernauts instantly heal based on the amount of surrounding enemies was extremely potent, pretty much ''rewarding'' ridiculous aggro magnets to [[LeeroyJenkins dive recklessly into enemy teams]] as the instant healing burst made them deceptively durable and able to easily destroy teams from the inside out, especially if they were built with health modification tools like Spirit Visage. Riot quickly nerfed the scaling as well as its damaging ability (which also gave them unnecessarily powerful waveclear), meaning the instant life-drain now has to be used more carefully.
*** Once Goredrinker fell by the wayside, Stridebreaker then took the crown as it came packaged with a short, but notable dash ability, ''and'' a bonus speed boost ''and'' the ability to slow nearby enemies hit, completely curbing the usual weaknesses of juggernauts' [[MightyGlacier lack of mobility]] by making engagement a no-brainer. This overly-loaded ability singlehandedly turned the likes of Garen and Darius into unstoppable freight trains that could outspeed even ranged lane bullies like Vayne or Teemo. Riot eventually realized their mistake and completely rid of the dash, reworking Stridebreaker more around its [=AoE=] slow as an [[AntiEscapeMechanism anti-enemy mobility tool]].

* Pre-season 12 introduced two new dragon types to the Rift, and while the Hextech Drake was generally accepted by the community as a fair addition, the '''Chemtech Drake'''... was not. Its respective {{Geo Effect|s}} -- shrouding the jungle in clouds of fog to near-permanently camoflage enemies ''and'' grant bonus damage to champions while fighting against enemies with higher health -- was considered enormously overpowered as it negated proper vision control, [[UnstableEquilibrium making it even harder for already-losing teams to regain control of their own side of the map]] (Riot attempted to remedy this by spawning more Scryer's Bloom plants to grant vision, but this was mainly seen as just a solution in search of a problem). The respective Chemtech Soul was also seen as pretty extreme, granting whoever owned it [[AutoRevive a temporary life upon death]], which was also seen as disproportionately powerful even to other Dragon Souls as teams with them were already generally harder to kill; [[TakingYouWithMe giving them a free means to finish off their opponents]] on top of the other benefits was seen as overkill. Once season 12 and the professional scene launched, the Chemtech Drake was quickly deemed an unstable terror, and so busted that Riot opted to disable it entirely during the middle of patch 12.2 to undergo significant tweaking, not showing up in any further capacity until season ''13''.

* Pre-season 12 introduced two new dragon types to the Rift, and while the Hextech Drake was generally accepted by the community as a fair addition, the '''Chemtech Drake'''... was not. Its respective {{Geo Effect|s}} -- shrouding the jungle in clouds of fog to near-permanently camoflage enemies ''and'' grant bonus damage to champions while fighting against enemies with higher health -- was considered enormously overpowered as it negated proper vision control, [[UnstableEquilibrium making it even harder for already-losing teams to regain control of their own side of the map]] (Riot attempted to remedy this by spawning more Scryer's Bloom plants to grant vision, but this was mainly seen as just a solution in search of a problem). The respective Chemtech Soul was also seen as pretty extreme, granting whoever owned it [[AutoRevive a temporary life upon death]], which was also seen as disproportionately powerful even to other Dragon Souls as teams with them were already generally harder to kill; [[TakingYouWithMe giving them a free means to finish off their opponents]] on top of the other benefits was seen as overkill. Once season 12 and the professional scene launched, the Chemtech Drake was quickly deemed an unstable terror, and so busted that Riot opted to disable it entirely during the middle of patch 12.2 to undergo significant tweaking.

** That said, current TF is considered a pretty balanced champion due to his very high skill cap. On the other side, beta Twisted Fate was the '''[[UpToEleven most broken champion to ever set its foot on Summoner's Rift]]'''. Why? Because his abilities, which are powerful enough to get him in this page on their current state, were ridiculously overloaded and made TF too threatening to the opposing team just for ''existing''. His Gold Card used to have the same [=AoE=] that his Red Card currently has, his passive gave everyone on his team a small critical chance, Destiny and Gate were two separate skills, Destiny slowed the enemy team globally, and Gate was global and accessible at level 1. Twisted Fate wasn't just overpowered, he was also frustrating due to his potential of cheesing an easy first blood through a surprise critical or just Gating to any point in the map, placing a ward and have his allies teleport to the ward for an ambush before the clock strikes the first minute.

** Something else worth noting is that around the end of season 5 and the beginning of season 6, his effective burst with his auto-attacks, Q and relatively-short-cooldown ultimate, his utility blind with his W and tankiness and mobility with his E, were all found to be great tools to make Graves an [[NotTheIntendedUse incredibly effective jungle bully.]] Around patch 6.2, he had the highest win rate, around 57%, [[UpToEleven in bot, top, and jungle, simultaneously.]] He received a few nerfs as of 6.3, and his win rate has dropped down, but time will tell if he'll stay there.

* Preseason 6 can easily be called "[[UpToEleven The Game Breaker Showdown]]" due to a LOT of overpowered champions, masteries and items:

* Pre-season 12 introduced two new dragon types to the Rift, and while the Hextech Drake was generally accepted by the community as a fair addition, the '''Chemtech Drake'''... was not. Its respective {{Geo Effect|s}} -- shrouding the jungle in clouds of fog to near-permanently camoflage enemies ''and'' grant bonus damage to champions while fighting against enemies with higher health -- was considered enormously overpowered as it negated proper vision control, [[UnstableEquilibrium making it even harder for already-losing teams to regain control of their own side of the map]] (Riot attempted to remedy this by spawning more Scryer's Bloom plants to grant vision, but this was mainly seen as just a solution in search of a problem). The respective Chemtech Soul was also seen as pretty extreme, granting whoever owned it [[AutoRevive a temporary life upon death]], which were also seen as disproportionately powerful even to other Dragon Souls as it gave an already-ahead team [[TakingYouWithMe even more means to finish off their opponents]]. Once season 12 and the professional scene launched, the Chemtech Drake was quickly deemed an unstable terror, and so busted that Riot opted to disable it entirely during the middle of patch 12.2 to undergo significant tweaking.

* Pre-season 12 introduced two new dragon types to the Rift, and while the Hextech Drake was generally accepted by the community as a fair addition, the '''Chemtech Drake'''... was not. Its respective {{Geo Effect|s}} -- shrouding the jungle in clouds of fog to near-permanently camoflage enemies ''and'' grant bonus damage to champions while fighting against enemies with higher health -- was considered enormously overpowered as it negated proper vision control, [[UnstableEquilibrium making it even harder for already-losing teams to regain control of their own side of the map]] (Riot attempted to remedy this by spawning more Scryer's Bloom plants to grant vision, but this was mainly seen as just an answer in search of a problem). The respective Chemtech Soul was also seen as pretty extreme, granting whoever owned it [[AutoRevive a temporary life upon death]], which were also seen as disproportionately powerful even to other Dragon Souls as it gave an already-ahead team [[TakingYouWithMe even more means to finish off their opponents]]. Once season 12 and the professional scene launched, the Chemtech Drake was quickly deemed an unstable terror, and so busted that Riot opted to disable it entirely during the middle of patch 12.2 to undergo significant tweaking.

* Pre-season 12 introduced two new dragon types to the Rift, and while the Hextech Drake was generally accepted by the community as a fair addition, the '''Chemtech Drake'''... was not. Its respective {{Geo Effect|s}} -- shrouding the jungle in clouds of fog to near-permanently camoflage enemies ''and'' grant bonus damage to champions while fighting against enemies with higher health -- was considered enormously overpowered as it negated proper vision control, [[UnstableEquilibrium making it even harder for already-losing teams to regain control of their own side of the map]]. The respective Chemtech Soul was also seen as pretty extreme, granting whoever owned it [[AutoRevive a temporary life upon death]], which were also seen as disproportionately powerful even to other Dragon Souls as it gave an already-ahead team [[TakingYouWithMe even more means to finish off their opponents]]. Once season 12 and the professional scene launched, the Chemtech Drake was quickly deemed an unstable terror, and so busted that Riot opted to disable it entirely during the middle of patch 12.2 to undergo significant tweaking.

* Reaching deep to Season 11, '''Omnivamp''' has slowly becomes this thanks to no part of champions that uses them well, like Aatrox, Vladimir, and Olaf. The ability to heal up damage dealt with either basic attack or ability that also scales with either physical damage or ability power makes survivability for these champions a no-brainer since they can either land their skillshots or brute force the enemy to death while also remain on near full health. It doesn't help that Riot also reworked most items and runestones that grants lifesteal or spell vamp to be omnivamps, like The Eclipse, Riftmaker, Conqueror, and Ravenous Hunter, making Aatrox and Olaf a nightmare to fight and subsequently requires you to get yourself one healing debuff source like Ignite or Bramble Vest. Riot eventually nerfed it in patch 11.6 so that omnivamp sources are lower compared to other healing sources even at full build, and make Ravenous Hunter have no base omnivamp and lowering each omnivamp gained for each stack.

* The newly revised item shop and itemization for Season 11 completely reworked almost every items in the game. The biggest changes came with the introduction of item tiers and categories, specifically the Mythic items that you can't have more that one of them in your inventory. While they are some exceptions, most of them are way powerful on it's release and it's constantly nerfed or readjusted across the preseason.
** Special mention goes to '''Eclipse'''. Turns out giving assassins a powerful percent health damage as well as safety on a relatively modest cooldown is just way too powerful for its own good. Combined with the bonus armor penetration from its mythic passive, as well as omnivamp as an icing at the top of the cake, it becomes a must buy for assassins and can be used as a niche pick for bruisers and marksmen too (like Pantheon, Jhin and Graves) thanks to the utility it gave for a short cooldown. Eventually it got nerfed by lowering its percent health damage bonus to six percent and lowering its movement speed bonus to fifteen percent, and then got nerfed again by lowering the shield value and increasing the cooldown for ranged champions.
** As a tradeoff that now Tiamat items loses the Crescent ability that allows the user to reset their auto attack when needed, the passive is now relegated to the new item Ironspike Whip. While Ironspike Whip is a relatively balanced purchase (if not underpowered), the same can't be said to the Mythic items it builds into, '''Goredrinker''' and '''Stridebreaker'''.
*** Goredrinker's new active allows you to heal a percentage amount of your attack damage per enemy champion hit, which also stacks with other healing modifier like Spirit Visage or Aatrox's ultimate, allowing you to almost heal your entire health bar in team fights. Champions that have innate sustain like Aatrox and Rhaast benefit greatly from it.
*** Meanwhile, Stridebreaker essentially makes engagement a no-brainer, as not only it increases your movement speed every time you hit an enemy alongside its mythic passive that grants you percentage bonus movement speed, its active allows you to dash forward a little and slash through your surrounding, while applying a good amount of slow to anyone hit, turning normally immobile juggernauts like Garen and Darius into unstoppable freight train that can outspeed even ranged lane bullies like Vayne or Teemo.

** Midseason 3 Kassadin, whose scaling was adjusted across the board, with crucial buffs being given towards ''Null Sphere'''s early-game scaling and ''[[WeaponisedTeleportation Riftwalk]]'''s late-game scaling. [[GoneHorriblyWrong This quickly turned out to be a huge mistake]], as not only did it make his late game obscenely more powerful, having a 1.5-second silence at level 1 made his early trading ability that much easier, making him almost completely unstoppable across the board. This cascaded into making him statistically ''the most relevant champion ever'' in both solo queue and pro play, with him a pick/ban presence in 95% of all games, earning him a dubious reputation of a character so powerful that virtually nobody was allowed to play him. Riot finally reworked him in early season 4 and significantly overhauled his abilities (namely replacing his silence with a short disrupt and a magic shield, reworking his ''Nether Blade'', and greatly toning down his ''Riftwalk''), which to this day has since put him at a surprisingly stable and decently balanced place, where he's still known as [[MagikarpPower a late-game monster]], but is significantly more manageable.

* Darius has split the community into the group that thinks he's just mediocre and the group that thinks he's a kill-stealing bastard that's just toxic to the game. To truly understand how bad this case is, one must understand that Darius's kit is built around his ultimate that instantly refreshes on a killing blow, and because it inflicts true damage, no amount of armor or magic resist can protect an enemy from him. At release Darius was far worse, with his passive stacks dealing absurd damage even at level 1, having mixed damage on his autoattacks making him hard to counter, and his ultimate originally had a half-second grace period after the dunk where if the victim died it would still refresh. This meant that the three or four sequential ults that were supposed to happen once in a blue moon if you were doing amazing were commonplace.
** It's not as bad anymore since Darius no longer does so much damage in multiple shots on the get-go via his most Juggernaut rework, but he's still a bit difficult to face in lane for some champions or in the late game if he applies his passive stacks fast enough.

* Skarner has had his ups and downs throughout his four-year history, but after the Juggernaut update, he became STUPID. A new passive that gives him absurdly fast and safe jungle clears and makes 1v1ing him absolutely suicidal (allowing him to invade with impunity and making his own jungle virtually impossible to safely invade without multiple teammates) mixed with great ratios and his already-high natural stats and growths and excellent scaling has turned him into the undisputed god of the jungle who starts off ridiculous (negating his historically unsafe early jungle) and quickly turns into an inexorable terror who spends the rest of the game running around and tearing everything that he can catch to bits. Riot made efforts to tone him down ''very'' quickly.

* Soraka became one in a very bizarre way during early 2020 (circa patch 10.2-3) as ''[[NotTheIntendedUse a solo top laner]]''. Around the time, it was found that [[WhiteMage Soraka]] (and also Sona to a degree) was able to keep pace with most toplaners thanks to her poke/self-sustaining kit (the top early-game was noted to be especially sluggish at that point in time), meaning that even if she was unlikely to kill opponents and "win" lane, [[WhyWontYouDie her survivability and utility ensured the same could also be said for her opposition]], and that [[TheMedic her healing]] by the teamfight phases would become even more powerful than if she was just a bot support. What makes this development interesting is how it wasn't born out of any single balance changes (her last prior buff was in ''July'' 2019) -- players in solo queue simply noticed how good she was in toplane, and once pros noticed the strategy, it caught on like wildfire and play/win/ban-rates skyrocketed until Riot finally took action and began nerfing the crap out of it.
** On the other side of the spectrum, Pantheon, normally a toplaner (or midlaner if playing against another assassin), finds himself in the similar case with Soraka in a rather comfortable spot as an ''[[NotTheIntendedUse engage support]]''. Aside of his early game mana issue, players find out that his point-and-click stun makes an excellent engage and strong counter against engage skillshot supports like Pyke, Leona, and Thresh. Combined with his high early damage and pressure on his Comet Spear and a his Aegis Assault, Pantheon can easily towerdive and secure kills for his botlane marksman or himself, while still retain high survivability and can NoSell turret shots. It takes Riot almost the entire year to figure out that he's way too oppressive while can still be played safe and had him finally readjusted to fit more as a solo laner again, namely by removing his Q Slow and the ability to deflect turret shot with his E and make him riskier to play aggressively. Time will tell if the current changes done to Pantheon does able to remove him from the duo lane and fixate his position as a solo laner again.
* As a general rule of thumb, [[MightyGlacier Juggernauts]] are prone to being this, as they're designed to be capable of wiping out multiple enemies at once at the cost of mobility. As such, if they're overpowered, they're ''really'' overpowered, being veritable [[OneManArmy One-Man Armies]] capable of annihilating entire teams on their own while still having the survivability of a tank. It's something of a trend for modern Juggernauts (i.e. Illaoi, Sett, the reworks for Aatrox and Mordekaiser) to be completely broken on release and gutted immediately.

** An oversight during the reworking of '''Muramana''' in the Preseason 11 causes it to trigger it's bonus physical damage based on a percentage of your maximum mana on any abilities, resulting in builds like AD Kassadin, Ryze, and Cassiopeia dealing hybrid damage from their skills and further empowering all champions that commonly build them like Kai'sa and Ezreal. Made even worse that '''Tear of the Goddess''' is now a starting item that you can build right off the bat alongside two potions instead of a Doran's item, allowing these champions to get their powerspike and essentially removing the need of mana management right at the start of the game. It eventually got patched so that it only triggers on basic attacks and abilities that deal physical damage, rendering the hybrid mage build moot, but still highly strong on Kai'sa and Ezreal.

** Special mention goes to '''Eclipse'''. Turns out giving assassins a powerful percent health damage as well as safety on a relatively modest cooldown is just way too powerful for it's own good. Combined with the bonus armor penetration from it's mythic passive, as well as omnivamp as an icing at the top of the cake, it becomes a must buy for assassins and can be used as a niche pick for bruisers and marksman too (like Pantheon, Jhin and Graves) thanks to the utility it gave for a short cooldown. Eventually it got nerfed by lowering it's percent health damage bonus to six percent and lowering it's movement speed bonus to fifteen percent, and then got nerfed again by lowering the shield value and increasing the cooldown for ranged champions.
** As a tradeoff that now Tiamat items loses the Crescent ability that allows the user to reset their auto attack when needed, the passive is now relegated to the new item Ironspike Whip. While Ironspike Whip is a relatively balanced purchase (if not underpowered), the same can't be said to the Mythic item it builds into, '''Goredrinker''' and '''Stridebreaker'''.
*** Goredrinker new active allows you to heal percentage amount of your attack damage per enemy champion hit, which also stacks with other healing modifier like Spirit Visage or Aatrox's ultimate, allowing you to almost heal your entire healthbar in teamfights. Champions that has innate sustain like Aatrox and Rhaast benefits greatly from it.
*** Meanwhile, Stridebreaker essentially makes engagement a no-brainer, as not only it increases your movement speed everytime you hit an enemy alongside it's mythic passive that grants you percentage bonus movement speed, it's active allows you to dash forward a little and slash through your surrounding, while applying a good amount of slow to anyone's hit, turning normally immobile juggernauts like Garen and Darius into unstoppable freight train that can outspeed even ranged lane bullies like Vayne or Teemo.
** By far the biggest contender of the most broken Mythic items in the game has to be the '''Sunfire Aegis''', which replaced the Sunfire Cape from the last patch. It removes the special passive that explodes upon immobilizing an enemy unit, but instead it accumulates damage over-time that stacks up to six times everytime it hit an enemy champion or epic monster before empowering your next basic attack that explodes and immolates the target. It immediately turns tanks into a walking fireball that outdamages even ''mages'' and ''assassins'' [=1v1=] while can still maintain good chunk of their health. It's so powerful that champions like Amumu and Cho'gath were able to solo Baron Nashor using it with the assistance of "Demonic Embrace", and an entire team building it would be able to [[https://www.youtube.com/watch?v=8IZAwiYu5gk microwave Baron Nashor by simply standing near it]]. Needless to say, it got nerfed for the entirety of the preseason, targeting it's natural bulkiness and base damage, before slowly lowering it's damage accumulation as for patch 10.25.

*** Trinity Force is largely identical to it's previous iteration, except now it grants you a damage amplifier that stacks everytime you hit your basic attack to an enemy champion. Combined with the triple damage burst and champs that can freely proc spellblade with it's ability, you can easily outdamages anyone that isn't buying the aforementioned Sunfire Aegis in a longer trades and sustained fights.

* [[http://leagueoflegends.wikia.com/wiki/Innervating_Locket Innervating Locket]] + [[http://leagueoflegends.wikia.com/wiki/Udyr Udyr]] was a combination so overpowered that it lead to Innervating Locket being removed from the game. To put it simply, the Locket gave heals when you used abilities, and Udyr is a melee fighter who uses his abilities a a lot. Udyr plus the Locket meant a powerful bruiser who also healed himself every few seconds and was nearly impossible to kill even if he wasn't building any tank items other than Innervating Locket.

* The remade Black Cleaver at the start of the Season 3 preseason period was arguably the most overpowered item in the history of the game. Giving huge damage, HP, cooldown reduction, armor penetration AND armor shred, Riot made it worse by inexplicably not making any of its stats Unique, meaning they could be stacked. It was not uncommon to see physical damage dealers buying boots and 4 Black Cleavers and wiping the floor with everyone else.
** Worse was that if combined with the % Armor Pen mastery and the Last Whisper, which also gives % Armor Pen, certain characters could buy a Black Cleaver and Last Whisper then run around dealing [[UnblockableAttack true damage]] to everything for most of the game. The irony was that not only was the Black Cleaver too good in terms of damage and armor pen, its intention of shredding armor became overshadowed by everything else (along with a subpar HP stat for bruisers) before it was remade in Season 5.

* The release of the Sated Devourer enchantment, which applies on-hit effects twice every other autoattack (later nerfed to every 4 autoattacks for ranged champions) made champions that had on-hit effects that dealt damage in a way (i.e. Vayne, Gnar, Corki, Ekko) has made those champions more viable for the jungle, or they're made more considerate of taking Smite as opposed to another summoner spell.

* Preseason 6 can easily be called "[[UpToEleven The Game Breaker Showdown]]" due to a LOT of overpowered champions, masteries and items:
** Remember what we said about Graves above? Riot reworked him along with other marksmen to give him a real unique identity as the [[ItMakesSenseInContext short-ranged marksman]]. They managed to do that - but at the same time they brought back EVERY problem that Graves had in his first release: his new Q dealt way too much damage, his E allowed him to stack his resistance passive way more effectively (while giving more resists!), not to mention it resetting too easily, and his autoattacks, which were supposed to deal more damage at point-blank range in a spread like his old Q, could KO an opponent with two or three attacks, with every other skill helping him to catch the opponent if fleeing (remember when we brought up Infinity Edge powering it up to more shots fired, folks?). Riot had to issue a hotfix for this one week after the Preseason started.
** Miss Fortune is right behind Graves as the most powerful marksman (or markswoman) after the reworks. She used to have a kit with weird scalings and one of the worst passives of the game, which gave her movement speed if she took no damage for a while. After the rework, she got an actually useful and powerful passive that deals extra damage on autoattacks, her W got her old passive added to its effects, and both her Q and ultimate got critical-related buffs which allow MF to deal a lot of damage to her opponents while farming AND insane wombo-comboing in teamfights. Guess how many patches after that she was nerfed.
** However, the "most broken thing in Preseason 6" trophy goes to Warlord's Bloodlust, a new offensive mastery from the Ferocity tree that heals for 15% of the damage done by critical strikes. What does it mean? Literally, Warlord's made Life Steal completely obsolete for carries, because all they needed was to rush critical chance items (which were also reworked so that ADC's could have higher critical chance) and heal any damage dealt to them with huge ease. And let's not get started on what champions like [[CriticalHitClass Yasuo, Master Yi and Tryndamere]] looked with this... Let's just say that every player rejoiced as Riot hotfixed the mastery so it only works on champions.
** Also from the Ferocity tree, the Deathfire Touch mastery seemed underwhelming at first. It gave damage per second on champions after they took damage from skills, but it was halved for area of effect skills, which basically every caster in the game has. Then people noticed how insane it was on DPS mages like Malzahar and ESPECIALLY Brand, since those skills will keep refreshing Deathfire Touch. Malzahar has three DPS skills that deal good damage and can sustain his mana without items thanks to one of them, Malefic Visions. Brand has his DPS damage coming from his passive, which not only deals max life % damage, but lasts 4 seconds and can be used to trigger a 2-second stun at LEVEL 2. Add Rylai's Crystal Scepter's slow and Liandry's Torment extra DPS (which Rylai amplifies) and it became very common to see those guys dealing two-thirds of anyone's life with a single skill.
** Guinsoo's Rageblade also got a rework...instantly making Jax batshit insane and any autoattack-reliant champion very powerful. The catch of the new rework is that melee autoattacks (on anything - the item would be balanced was this only valid against champions) give 2 of 8 stacks to the item. Coupled with Sated Devourer and its attack speed, it took just three attacks to reach max stacks. ButWaitTheresMore. As the new Guinsoo reaches 8 stacks, it starts to deal [=AoE=] damage scaling with both AD and AP, a thing that most of the champions that benefit of the item lacked (making it akin to Ravenous Hydra's passive). ButWaitTheresMore Also slightly reworked, Hextech Gunblade heals for 15% of ALL damage dealt, allowing for insane healing in teamfights while dealing tons of [=AoE=] damage. [[OverlyLongGag But Wait, There's Even More!]] The last mastery of the Ferocity tree is Fervor of Battle, which, [[RuleOfThree just like Warlord's Bloodlust and Guinsoo's Rageblade]], stacks when autoattacking anything, ramping even more damage over the already huge benefits. This combination allowed for some unbelievable things that made most of the involved items and masteries get hit by the nerf hammer.
* Before it was changed heavily, the AP jungler item, Runeglaive, was insane on Ezreal. What the item did at the time was it gave you a Sheen style proc (an item that was already amazing on Ezreal) with a slightly lower AP ratio but with a small [=AoE=] slapped on. What resulted from this? Ezreal's running smite, granting their team a bunch of extra control on dragon and baron, an earlier power-spike due to it being cheaper than Lich Bane, and unprecedented wave clear, the major weakness AP Ezreal had over AD Ezreal. Oh, and it also restored missing mana.

* Rylai's Crystal Scepter from patch 5.13. The item was formely a niche pick and core only in certain champions such as Rumble. Then the slow values on the item and the slow mechanics of the game were reworked, and Rylai became the best item on AP champions, bar none. Not only the stats the item provides are godly for the squishy AP carries, its slow helps them to kite or catch threats easily. Champions that can abuse the item such as Azir, Viktor and Brand became way more powerful than before the patch just because Rylai was that ridiculous, and nowadays even champions with solid crowd control options on their kit, such as Syndra and Vel'Koz, are buying the item. It finally got nerfed on patch 6.23, bringing down many champions that relied on the item, and changing build paths for the ones who didn't.

* Spear of Shojin (and to an extent, the old Essence Reaver passive that eventually got moved to Shojin in patch [=9.3=]) was one of the items introduced alongside Nexus Blitz in Season 9. Initially, the item was meant to be a tank item that reduces damage dealt towards the user on teamfights. However, Riot reworked the item by moving the old Essence Reaver's passive onto this item, resulting in the item becoming a go-to item for almost every on-hit bruisers that allows them to swiftly replenishes their ability cooldowns by 20% on basic attacks simply by activating their ultimate. Combined with the item being a powerful stat-stick that provides 60 attack damage and rather generous 20% cooldown reduction, it basically allows champs like Jax and Riven to be a pain in the ass to fight against, as they were able to gain sustained damage and tankiness by simply rushing on their first or second buy. It was later removed from the game at the end of the season 9, then re-added again in the refurbished Nexus Blitz using it's old stats and eventually removed from the game for good. The Awakened Dragon passive was later reintroduced in the new item for Season 11 item "Navori Quickblades", except that outside of being active all the time instead of being tied with your ultimate, now it requires you to critically strikes using basic attack or abilities that does proc critical strikes (like Yasuo's Q), and it's now a crit item that does no longer provide additional attack damage, which considering the change of critical formula in Season 11 itemization, it pretty much neutered it's power play by a lot.

** '''The Collector''' is just a hybrid Critical chance and Lethality item that doesn't stand out on it's own have it's not because of it's passive, which allows the user to execute any target below 5% health on their next attack and grant extra 25 gold per kill that just so happens to work against a lane minion, allowing the user to reach their third item much easier. It syncs well with AD carries that doesn't always had to resort on critical chance like Jhin, Samira, Miss Fortune, and even Gankplank. It was eventually nerfed and no longer be able to execute minions and only work against champions, but the execute damage is still a welcomed addition to secure kills, even against tanks.

*** Divine Sunderer trades off the triple attack damage proc with the target's percentage health bonus physical damage on proc with a ''minimum'' damage of ''a hundred fifty percent'' attack damage, as well as a spell vamp that heals melee champs that procs it for fifty percent of the pre-mitigation bonus damage dealt. It suddenly turns champions with normally sustained trade to longer engages like Jax and Hecarim into a powerful burst machine that can easily outdone any tanks and squishies alike much quicker while can also sustain themselves with moderate healing if you so proc it on an enemy champion. The Target percentage health bonus damage [[GoodBadBugs also procs on turrets for some reason]], making it a powerful splitpush machine until it's fixed a patch after.

** Special mention goes to '''Eclipse'''. Turns out giving assassins a powerful percent health damage as well as safety on a relatively modest cooldown is just way too powerful for it's own good. Combined with the bonus armor penetration from it's mythic passive, as well as omnivamp as an icing at the top of the cake, it becomes a must buy for assassins and can be used as a niche pick for bruisers and marksman too (like Pantheon, Jhin and Graves) thanks to the utility it gave for a short cooldown. Eventually it got nerfed by lowering it's percent health damage bonus to six percent and lowering it's movement speed bonus to fifteen percent, and then got nerfed again by lowering the shield value and increasing the cooldown for ranged champions.

* As a general rule of thumb, [[MightyGlacier Juggernauts]] are prone to being this, as they're designed to be capable of wiping out multiple enemies at once at the cost of mobility. As such, if they're overpowered, they're ''really'' overpowered, being veritable [[OneManArmy One-Man Armies]] capable of annihilating entire teams on their own while still having the survivability of a tank. It's something of a trend for modern Juggernauts (i.e. Illaoi, Sett, the reworks for Aatrox and Mordekaiser) to be completely broken on release and gutted immediately.

It is inevitable, given the competition-oriented gameplay. ''League of Legends'' is actually designed around the "[[FakeBalance perfect imbalance]]" paradigm -- the game is always slightly favors one particular strategy over another, but not too much to render any other strategy impossible, which prevents the game from getting old and repetitive as the balance shifts between different strategies.

It is inevitable, given the competition-oriented gameplay. Who/What exactly is one constantly changes, due to rapid updates, and what exactly is a "GameBreaker" is massively different depending on your level of play. ''League of Legends'' is actually designed around the "[[FakeBalance perfect imbalance]]" paradigm -- the game is always slightly favors one particular strategy over another, but not too much to render any other strategy impossible, which prevents the game from getting old and repetitive as the balance shifts between different strategies.

* Soraka became one in a very bizarre way during early 2020 (circa patch 10.2-3) as ''[[NotTheIntendedUse a solo top laner]]''. Around the time, it was found that [[WhiteMage Soraka]] (and also Sona to a degree) was able to keep pace with most toplaners thanks to her poke/self-sustaining kit (the top early-game was noted to be especially sluggish at that point in time), meaning that even if she was unlikely to kill opponents and "win" lane, [[WhyWontYouDie her survivability and utility ensured the same could also be said for her opposition]], and that [[TheMedic her healing]] by the teamfight phases would become even more powerful than if she was just a bot support. What makes this development interesting is how it wasn't born out of any single balance changes (her last prior buff was in ''July'' 2019) -- players in solo queue simply noticed how good she was in toplane, and once pros noticed the strategy, it caught on like wildfire and play/win/ban-rates skyrocketed until Riot finally took action and began nerfing the crap out of it.

* Pre-Rework Poppy was half- GameBreaker, half JokeCharacter. Her farming was terrible and her early game pathetic- but if she managed to get herself some items, she became a hammer-wielding murder machine with her ridiculous passive and ult. Her passive made her incredibly tanky, and her ultimate made her immune to ''everything'' except one enemy champion. If she attacked any other champions, they were basically helpless for 8 seconds (the idea was that Poppy would force herself into a one-on-one fight with another champion, but failed to specify that Poppy had to attack the champion she targeted). She ended up completely reworked, with her kit stabilized so Poppy isn't so divided between completely useless and completely overpowered.

* Rylai's Crystal Scepter from patch 5.13. The item was formely a niche pick and core only in certain champions such as Rumble. Then the slow values on the item and the slow mechanics of the game were reworked, and Rylai became the best item on AP champions, bar none. Not only the stats the item provides are godly for the squishy AP carries, its slow helps them to kite or catch threats easily. Champions that can abuse the item such as Azir, Viktor and Brand became way more powerful than before the patch just because Rylai was that ridiculous, and nowadays even champions with solid crowd control options on their kit, such as Syndra and Vel'Koz, are buying the item. It finally got nerfed on patch 6.23, bringing down many champions that relied on the item, and changing build paths for the ones who didn't.

* [[http://leagueoflegends.wikia.com/wiki/Innervating_Locket Innervating Locket]] + [[http://leagueoflegends.wikia.com/wiki/Udyr Udyr]] was a combination so overpowered that it lead to Innervating Locket being removed from the game. To put it simply, the Locket gave heals when you used abilities, and Udyr is a melee fighter who uses his abilities a a lot. Udyr plus the Locket meant a powerful bruiser who also healed himself every few seconds.

* Since his release, Azir has had a number of notable bugs that frequently had to be fixed. But as soon as people got past the said bugs and realized his potential, he THEN got nerfed so many times that one can't count in both hands. His kit revolves around summoning Sand Soldiers, untargetable units that may auto-attack for Azir, dealing magic damage per attack. Since it scales with attack speed, a fed Azir can and will deal lots of damage per second on late game from far away. His ultimate also gives him a second chance if he fails to keep someone away, pushing enemies back and creating a wall on the location. With everything, Azir has a lot of play potential, either closing the door whenever his team is being chased, either Insec'ing the entire opposing team, either just dealing slow and damage thanks to Rylai's Crystal Scepter being ridiculously good on him. It's no hyperbole to say that every single skill of him has already been nerfed and this fails to stop Azir from being an amazing champion in the hands of any good player. Keep in mind: Riot usually nerfs champions that sit on winrates around 55% or higher. Before Azir's latest nerfs, his winrate was so low as 42%. And he was still broken enough for him to deserve the nerfs. That's to say something.

* [[http://leagueoflegends.wikia.com/wiki/Innervating_Locket Innervating Locket]] + [[http://leagueoflegends.wikia.com/wiki/Udyr Udyr]] was a combination so overpowered that it lead to Innervating Locket being removed from the game.

** Then there's the ''Uncle Fate'' build, using [[{{Multishot}} Runaan's Hurricane]], [[LifeDrain Bloodthirster]], and Nashor's Tooth mixing with Attack Speed. Cue Twisted Fate being even MORE broken as his '''E''' links up with Runaan's Hurricane and Nashor's Tooth, leading to him outright nuking unwitting victims with AD and AP damage.

* Morgana's Black Shield, for its ability to make the target temporarily immune to all forms of crowd control (an ''incredibly'' powerful ability given how much of a major role these play in the game).
* It's been notoriously hard to balance Mundo on Twisted Treeline... but he's unlikely to be fixed, as Riven, Shyvana, Poppy, Mordekaiser and especially Singed have begun to overshadow him at the time that was discovered.

** It's not as bad anymore since Darius no longer does so much damage in multiple shots on the get-go via his most recent rework, but he's still a bit difficult to face in lane for some champions or in the late game if he applies his passive stacks fast enough.
* Zyra and Jayce were both considered overpowered on release, the former far more so than the latter. They were both considered to be the best champs for their lanes (mid and top, respectively) by a long shot. Zyra had ludicrous burst even with minimal AP, a LONG-ranged snare with an incredibly fast travel speed, untouchable poke and zoning, and tank-tier initiation, not to mention incredible scaling and further teamfight utility. She received the single largest nerf in League history but still remained one of the best mages in the game, something that attests to how ridiculous she was on release. As for Jayce, he was virtually unbeatable top thanks to being almost completely unapproachable and impossible to duel or even trade with due to his hammer form E, a low-cost knockback on a very low cooldown that also hurt like a bitch, while his cannon form sported incredible poking and burst that was even more effective in the melee-heavy top environment. He also snowballed fast and hard and became an utter terror when fed, essentially becoming a second carry. His nerfs, while certainly justified, were nowhere near as heavy as hers, but that was mostly because you could at least do okay and farm against him top, while the best that you could do against Zyra was survive.
** Ironically however, Jayce's late game is nowadays in a bad spot in the current meta, while Zyra had a slight rework as of 6.9. However, the recent preseason with the new Lethality stat added plus a few minor changes has made Jayce a little more balanced.

** Then the Rengar after said nerfs still ended up being this, in the sense that his "triple Q" exploit (involving ulting, readying Savagery, then using Empowered Savagery JUST as Savagery comes off cooldown then using Savagery again for massive damage and attack speed to follow up) is quite capable of outright eviscerating a squishy champion. Cue him being part of the recent preseason assassin reworks, and people are still complaining about Rengar's power, though at this point he may be much easier to balance.

* Blitzcrank is often banned at low [=ELOs=] because his trademark move, "Rocket Grab", is one of the most powerful initiators in the game, as a move that can near instantly grapple an enemy and draw them to you, which, when used in conjunction with teamfighting, will often lead to a quick death for (if the Blitz is competent) usually either the support or more often the AD carry. Higher [=ELOs=] tend to pass over him, as Blitzcrank is often cited as DifficultButAwesome, and that really competent ones are rare enough that banning him constantly is usually worthless compared to someone like, say, Thresh.
* Unlike every other support (or champion in general) in the game, Thresh does not gain Armor on level up. However, this is remedied by his passive: every time a small monster or minion dies, they have a chance of dropping a soul, whereas champions and large monsters always drop them. Thresh can move near a soul to obtain it, which permanently grants him Armor and Ability Power, and there is no limit to how many souls he can grab. Essentially, this means there is no limit to how much Armor and Ability Power he can have, and he is the only support in the game that gets stronger by allowing his friendly AD carry teammate to farm without farming himself. Thresh's Q is Death Sentence, which is basically Blitzcrank's grab, but with a slightly shorter range, a slower pull-in, a lower cooldown, and with the additional option for Thresh to immediately jump to his victim's current position. But wait, there's more! The most infamous (and hated) thing about Thresh is his W, Dark Passage, AKA "the lantern." Thresh throws his lantern towards a spot of his choosing, where it stays for up to 6 seconds. If an ally right-clicks it, the lantern disappears and the ally is pulled right to Thresh, essentially giving his ally a reset button to erase any mistake they make. While the lantern is active, all allies near it gain a shield for up to 4 seconds that absorbs all forms of damage, with the shield getting stronger the more Ability Power Thresh has. Thresh's E is Flay, which passively gives him bonus magic damage (again scaling off his AP) on each autoattack he lands - and keep in mind Thresh's autoattacks are long range. He can also activate Flay to either knock all enemies in a cone AWAY from him, or all enemies in a cone TOWARD him, as well as slowing them for about 2 seconds. Thresh's ultimate is simply "The Box," which places a pentagon made of green energy walls around him: when an enemy runs into a wall, it disappears, inflicting massive damage (scaling with his AP), and slowing them by 99% for 2 seconds, and while the damage and slow will be halved, enemies CAN be affected by more than one wall. Thresh is the single-most picked support champion in the game, but given his kit and passive, he can quite easily fill ANY role his team needs. Common complaints are that if not for his lantern, Thresh would be acceptable, but his entire kit as-is simply gives too much.
* On Dominion and Twisted Treeline there are several, but none have ever come close to Kassadin.
** To clarify: Kassadin has high utility, high damage, and good mobility. His traditional weakness is that he's squishy. Players realized he could build defensive mana, magic penetration, and cooldown reduction items, abuse his ult's stacking damage and low cooldown, and abuse the wall-heavy configuration of the Dominion map for even stronger mobility, still-potent damage, and still-potent utility--with none of the tendency to blow up if focused. His mobility was by far the worst part of him--to the point that he can practically be everywhere on the map at once. He was so infamous that he was the first champion on Dominion to receive map-specific nerfing. The first nerfs he has received have simply made his power level comparable to that of other truly OP champions, but later nerfs have ''finally'' brought him down to within reason, or worse, made him much less viable than ever. However, he's receiving a few quality changes that make him see a bit more play again on the other maps. Up to seasons 5-to-6, he's in a balanced spot where he's still very item-dependent and has a rough time early game, especially against zoners.
** Jayce, Nidalee, and Kha'Zix are the next three after Kassadin on Dominion. They are not at the same level as Kassadin, but are certainly headaches. Lulu, Talon, Wukong, Rengar, and Teemo have all had their times in the "spotlight." Zyra, Amumu, remade Evelynn, and remade Karma have been consistently high-tier.
** Then there's [=LeBlanc=]. As a remarkably powerful assassin, she could burst you down in an instant once she got going, and there was no counterplay since you spent the entire time silenced. Fortunately, Riot has since removed her silence, so there's a possibility of actually fighting back before you get deleted.
** In a bit of irony, the aforementioned Thresh was practically a JokeCharacter on Dominion. Not only did he have to go out of his way to utilize the aforementioned soul mechanic (leaving him squishy), his high cooldowns did not sit well on a map where turrets "die" in ten seconds, and his lantern was significantly less powerful when Thresh couldn't risk heading into initiation range. However, he's since gotten a map-specific buff (souls now give him two stacks of Damnation) which made him unremarkable top but fairly strong bot.

* In the Pre-Season 5 the jungle was overhauled, and most of the monsters, including dragon, have a new style to their attacks. Why is this important? Because Pantheon's passive, which blocks certain kinds of attacks, blocks ALL of Dragon's attacks. This means Pantheon can take Dragon at ''LEVEL 2''. ''ALONE''. Thats right, 2 minutes into the game a Pantheon can solo the Dragon and secure a big buff for his team.
** To a lesser extent, this can also work with Fiora using her skill Riposte, which can deflect a Dragon's attack, but only when timed right. Apparently with her reworked version, it may do the job a bit better than expected, especially with her rising dominance in top lane.
* Warwick emerged as THE strongest jungler after the overhaul, no competition. Not only does his sustain make him insanely safe, one of the newer jungle items, Skirmisher's Sabre, allows you to deal true damage for a few seconds and it counts as an on-hit effect. Couple this with the Devourer enchantment, which gives infinitely scaling on-hit magic damage. All Warwick has to do is walk up, smite a carry and use his ultimate, which applies on-hit effects, repeatedly. That carry is now dead. Period. This turned out to be so broken that within 2 weeks Warwick went from a champion people left games over because he was TheLoad, to a champion with a ''92% ban rate''. Riot started rolling out hefty nerfs on his ultimate VERY quickly.
* Due to MR nerfs in season 5, ranged AP champions that go top lane and some in mid end up being this due to difficulty to engage.

*** Recently, Warlord's was changed to only heal for a percent of missing HP while no longer giving attack speed; it was pointed out that it was rather useless either way unless you had crit from items and runes, meaning you barely had anything to go by early game compared to the other keystone masteries.

** Guinsoo's Rageblade also got a rework...instantly making Jax batshit insane and any autoattack-reliant champion very powerful. The catch of the new rework is that melee autoattacks (on anything - the item would be balanced was this only valid against champions) give 2 of 8 stacks to the item. Coupled with Sated Devourer and its attack speed, it took just three attacks to reach max stacks. ButWaitTheresMore. As the new Guinsoo reaches 8 stacks, it starts to deal [=AoE=] damage scaling with both AD and AP, a thing that most of the champions that benefit of the item lacked (making it akin to Ravenous Hydra's passive). ButWaitTheresMore Also slightly reworked, Hextech Gunblade heals for 15% of ALL damage dealt, allowing for insane healing in teamfights while dealing tons of [=AoE=] damage. [[OverlyLongGag But Wait, There's Even More!]] The last mastery of the Ferocity tree is Fervor of Battle, which, [[RuleOfThree just like Warlord's Bloodlust and Guinsoo's Rageblade]], stacks when autoattacking anything, ramping even more damage over the already huge benefits. This combination allowed for some unbelievable things that made most of the involved items and masteries get hit by the nerf hammer (most recent 5.24 patch tweaked its [=AoE=] range to be lower). [[ArsonMurderAndJaywalking On a smaller note, it also made AP Master Yi a thing again]].
*** ... [[LethalJokeCharacter except it turned out to NOT be a smaller note.]] Due to his passive which allows double-procs, his jungle proficiency and his ridiculous late-game, people ended up realizing they could build Master Yi with Devourer-Guinsoo, stack everything in a blink of an eye and build tank for the rest of the game, effectively doing anything that a normal Master Yi does without the glass cannon downside AND with hybrid damage to boot. Xin Zhao also got a buff on the same meantime that allowed him to do the same thing while ALSO negating his biggest weakness (the late game, in this case). The madness only ended once Riot fused Devourer and Guinsoo in one item, giving Guinsoo the Phantom Hit passive and replacing Devourer with a generic version of Blade of the Ruined King for junglers (the return of the Bloodrazor AKA Madred's).
*** Regarding Fervor of Battle, a keystone mastery that grants stacks for every attack landed on an enemy champion that increases auto-attack damage per stack, the mastery is quite abuse-able by nearly ANY on-hit AD caster; any AD champion with auto-attack-based abilities could gain a ton of stacks to deal so much extra damage, especially when combined with certain items (such as Blade of the Ruined King or any Spellblade item, along with Black Cleaver). While it was rare for them to use such items to such effects (they mainly relied on more raw damage and cooldown reduction items), could easily lead to a lot of monstrous damage built-up from a very quick combo of a normal auto, one damaging spell, then followed up with their main on-hit/auto-attack ability. Examples included Rengar's Q, Wukong's Q, Renekton's W, Yasuo's Q and so forth. Basically, any on-hit AD caster champion that could attack with a rapid-ton of both autos and spells could heavily abuse this with late game burst damage comparable to both the DPS-type champs it was meant for along with Thunderlord's Decree, which was ironically the [[ComplacentGamingSyndrome one thing that prevented Fervor from getting as much exposure on those said AD casters during that timespan]]. Even then, Riot rolled nerfs to Fervor just to prevent it from being abused like so overall, but it was still very strong since each hit landed granted anything but a single stack (abilities used to grant 3 stacks on-hit instead of 2 before getting nerfed, and the passive prior to that went up to 10 stacks total instead of 8 as of today, and could even be stacked on non-champion targets when it first debuted). Recently however, it was reworked in the 7th preseason to grant AD per stack instead of auto-attack damage, making it easier to manage while still being beneficial to such champions, though recently having abilities no longer proc it allows for less opportunities for those said AD casters to abuse it unless they stay in a fight for a quite a while (ADC's on the other hand, still only apply 1 stack per hit meaning it's no longer as effective for them....at first).
** Illaoi got released on the meantime of the Preseason, and struck top lane like a meteor. Her supposed weakness was that she had to stay still in an area to deal damage, but she dealt too much freakin' damage in said area. Her E, Test of Spirit, works just like Blitzcrank's Rocket Grab, but instead of grabbing the champion itself, it grabs its soul for her team to beat up, not only removing the no-safety factor of dragging, say, Amumu to the middle of everyone, but also forcing the grabbed champion to fight if he doesn't want to spawn tentacles from out of nowhere. And her tentacles not only deal a lot of damage, but also heal Illaoi for missing health when hitting champions. [[https://www.youtube.com/watch?v=etbP-JAhdps If that doesn't convince you of her brokeness, what about a video of Illaoi getting a Pentakill 1vs5 while her team is 18 kills behind?]] Ever since the new Dynamic Queue, she's been almost banned non-stop.
*** On the other hand, Illaoi has maintained a win ratio below 50% since her release. She's rarely picked for her substantial weakness of having very little crowd control and no way to force enemies to stay within her zone of damage, and unlike Heimerdinger she can't manually put down turrets to compensate for this weakness. This makes for an easily-ignored wall of health points that contributes little to her team post laning phase. These days, from low elo to high, Illaoi is considered a weak pick.
*** It turns out that Illaoi ended averting GameBreaker on high elos due to her "UpToEleven MightyGlacier" style, which does not fit at all with high level playing. However, in low elos, she's absolutely insane, as newbie players probably will not realize how much good ignoring Illaoi or killing her tentacles does, not to mention that they get WAY more frustrated with Test of Spirit. This means that Riot cannot buff her without being extremely careful, otherwise she'll just be permabanned anywhere above Gold V only for her to be playable on Diamond elo.

* Tank Ekko was running rampant until a large number of changes to his ability scalings. Before these changes, Ekko's base damage was so high, along with having passive execute damage, Ekko could build full tank and go toe-to-toe with anyone while being nigh-unkillable since his ultimate healed him for a percentage of damage he'd taken in the past 4 seconds. Tack onto this incredible mobility and respectable CC, Ekko terrorized the top and middle lanes until his bases were gutted and his ratios buffed in an attempt to shoehorn him into a slightly less frustrating assassin role, rather than an invincible super soldier that required four people to kill.
** Release Ekko was completely broken as an AP carry, able to kill basically everything after proc'ing his passive. Thus, Riot nerfed his numbers and AP ratios so that he was still a good pick, but not broken. Then people discovered tank Ekko and they were forced to nerf Ekko into a lower state. A while after, they tried to give him some power back, but tank Ekko instantly returned and took over the scene, forcing Riot to buff THE VERY SAME RATIOS that they nerfed on release Ekko in exchange for base damage. The TL;DR of this is that Riot has a huge problem with balancing Ekko, because one misstep will give players a lot of problems with 2 second stuns and close-to-death tanks escaping fights pressing one button.
*** The aforementioned Fervor of Battle before it got reworked in the 7th preseason was even abused on Ekko for his recent Trinity Force build even, despite Fervor tailoring to AD-based auto-attack damage and Ekko's on-hit default passive, W passive and E proc all being on-hit magic damage. That's saying something.
* Speaking about tank assassins, they're a problem by itself. Assassins should do their job of deleting one of the opposing carries fast and cleanly, having tools for getting in and out of the fight to do so and being instantly blown up if they fail due to squishyness. Obviously, if they're not squishy, this means that they can simply do anything they want without caring for the downsides, and often they become even more of a threat than his usual builds, since their tools for getting out can be used to assassinate more targets. Nidalee, Fizz, Yasuo and the aforementioned Ekko have each of them found sucess with such builds, and thus they've been nerfed on their durability and base damages.
* The Juggernaut patch had Skarner getting hotfixed. The Marksman patch had Graves. You would think that Riot would avert RuleOfThree and not make the same mistake during the Mage patch, rig- oh, is that a Malzahar hotfix nerf? His rework wasn't even that bad, since it kept his most iconic abilities and his "infect and attack" playstyle, however his new W allows him to summon swarms of Voidlings with ease, which means that jungle Malzahar became Elise (worth of note that she was almost a GameBreaker on her own) with lesser ganks and a lot of extra damage, not to mention one of the best ultimates on the game. And his passive gives him a free Banshee's Veil every few seconds.
* Swain deserves a more detailed explanation. Before the mage rework, he used to have huge question marks on his skill order: his Q was supposed to be his main damage tool, however most of the players maxed either W for being his only non-ultimate waveclear or E for amplifying his other skills' damage and scaling way better with level points. After the rework, Riot adjusted this so that it was more attractive to max Q, but no one realized this, and together with bad numbers, his win rate plummeted. Thus, Riot buffed his numbers, reworked the heal on his ultimate and basically '''implored''' to players to max Q. [[GoneHorriblyRight It worked out a bit too well, making Swain an unkillable damage machine.]]
* Since his release, Azir has had a number of notable bugs that frequently had to be fixed. But as soon as people got past the said bugs and realized his potential, he THEN got nerfed so many times that one can't count in both hands. His kit revolves around summoning Sand Soldiers, untargetable units that may auto-attack for Azir, dealing magic damage per attack. Since it scales with attack speed, a fed Azir can and will deal lots of damage per second on late game from far away. His ultimate also gives him a second chance if he fails to keep someone away, pushing enemies back and creating a wall on the location. With everything, Azir has a lot of play potential, either closing the door whenever his team is being chased, either Insec'ing the entire opposing team, either just dealing slow and damage thanks to Rylai's Crystal Scepter being ridiculously good on him. It's no hyperbole to say that every single skill of him has already been nerfed and this fails to stop Azir from being an amazing champion in the hands of any good player.
** Keep in mind something: Riot usually nerfs champions that sit on winrates around 55% or higher. Before Azir's latest nerfs, his winrate was so low as 42%. And he was still broken enough for him to deserve the nerfs. That's to say something.
* [[AttackAttackAttack Kled]]. The Redneck Noxian Yordle has some pretty unique mechanics: he has a mount called Skaarl that leaves him when her health bar is depleted, and that leaves Kled as a sitting duck until his resource, Courage, reaches 100, when Skaarl returns. He also has a powerful W skill that buffs his autoattacks with more damage and speed. Thus, Kled stops being a threat when he loses Skaarl... until you give him [[LifeDrain life steal items]]. All of a sudden, Kled instantly becomes insane, healing Skaarl with every single one of Kled's autos and giving him a stronger "shield" than his own ult (which is also HUGE, as it grants an engage or the opposing team fleeing under the threat of a massive-shielded Kled and his allies following him). And the more the game progresses, Kled becomes harder and harder to get off of Skaarl, [[WhyWontYouDie let alone being killed.]] Should we also mention that Kled's damage on his W was on-hit HP-based with extra attack speed? Meaning he could make use of items like Blade of the Ruined King and/or Black Cleaver to DPS-shred-burst his target to death?
* Rylai's Crystal Scepter from patch 5.13. The item was formely a niche pick and core only in certain champions such as Rumble. Then the slow values on the item and the slow mechanics of the game were reworked, and Rylai became the best item on AP champions, bar none. Not only the stats the item provides are godly for the squishy AP carries, its slow helps them to kite or catch threats easily. Champions that can abuse the item such as Azir, Viktor and Brand became way more powerful than before the patch just because Rylai was that ridiculous, and nowadays even champions with solid crowd control options on their kit, such as Syndra and Vel'Koz, are buying the item. It finally got nerfed on patch 6.23, bringing down many champions that relied on the item, and changing build paths for the ones who didn't.
* Camille, whose kit is so overloaded and overpowered, it's almost as if Riot created her intending for her to be Irelia 2.0 and the new goddess of the top lane. To start, her passive is a shield that activates when she attacks an enemy (Unlike Yasuo's whose shield activates when he takes damage, giving her the ability to trade on her terms), and hers scales with her maximum health, and the shield's type changes to the type of damage her attacker deals mostly (So, if she's attacked by a physical damage champion, the shield becomes physical), with the cooldown on this shield a mere 20 seconds on rank 1, getting lower as she levels up. Her Q is an auto-attack boost, can be used twice for no cost, and, in the second hit, transforms 40 to 100% of the bonus physical damage to TRUE DAMAGE on rank 5, and, like all auto-attack boosters, resets her AA time and procs on-hit effects such as Spellblade and lifesteal, ON BOTH HITS. Her W is an area-of-effect damage that, when hitting enemies in the outer-half, slows them and deals max health percent physical damage AND restores HP for the same amount for each enemy hit (And, let's remember, we're on the tank meta, where people usually have large HP pools). Her E is a gap closer that, like her Q, can be used twice, and the second half gets a boost to the maximum range if you travel towards a champion, while also stunning and dealing damage to everyone on arrival, AND giving Camille an auto-attack speed bonus for a few seconds after she lands. Lastly, her ultimate is literally "1v1 ME, BITCH" that creates a small hexagon around her target, knocking back every other enemy, and, while in that area, Camille's auto-attacks deal bonus max health percent magical damage to the target, and, unlike every other "terrain" ability, the targeted enemy cannot get out of it, PERIOD (The only way to end her ultimate is having Camille leaving the area, either by her will or by a knockback ability). With few weaknesses (Champions that deal mixed damage, champions that can block/dodge auto attacks, and heavy CC/knockback) and too many tools on her kit, she's literally on the path to become the new Irelia, being a perfect bruiser who can easily gapclose, explode squishies and melt tanks while dealing all types of damage, and doing all this building Trinity Force, [=BotRK=], and then tanky to become literally unkillable. To further illustrate her "overpoweredness": No more than a few days after her release, and she's already received minor nerfs, because even in the early game, which was supposed to be a weakness, she was still pressuring people too much, and even now she's still a monster to face. It's no wonder she was once an absolute pick-ban champion on all elos, and that's saying something.
* Zoe. Her Q is a projectile that can be redirected much like Orianna's ball, with damage that scales with range and can ramp up to absolutely insane levels for a single ability, to the point that a capped Q can erase 40-50% of most lane opponents' health '''from level 1'''. Her W lets her use summoner spells and item casts recently used by other champions on demand, allowing her to use both her allies and her enemies' strengths against the latter. Her E is the first ability in the game to induce sleep, which is a combination slow and stun that is broken on damage but doubles the damage of the next attack or ability that hits the victim (to a cap), and the projectile goes over walls, allowing her to make easy surprise attacks. If it hits nothing, it briefly becomes a puddle on the ground that induces the status to anything that walks into it, which is quite unique for a skillshot, and its cooldown is lowered on hitting a champion. Like any other champion with a hard CC on a basic ability (Lux, Morgana, Anivia, etc.), chasing her is an exercise in futility because of her E and her naturally high movement speed, but like Singed, it's also outright suicidal because the damage from her E+Q combo lets her destroy pursuers even faster than him. Lastly, her ult is a low cooldown blink that lets her teleport to a location for a second and teleport back, allowing her to dodge skillshots, make hit-and-run attacks with relative impunity, or just fake out opponents. This ultimately makes for a champ that is frustrating to fight because of her being so hard to punish due to having damage out the ass with the CC and mobility to complement it.

* Zoe. Her Q is a projectile that can be redirected much like Orianna's ball, with damage that scales with range and can ramp up to absolutely insane levels for a single ability, to the point that a capped Q can erase 40-50% of most lane opponents' health '''from level 1'''. Her W lets her use summoner spells and item casts recently used by other champions on demand, allowing her to use both her allies and her enemies' strengths against the latter. Her E is the first ability in the game to induce sleep, which is a combination slow and stun that is broken on damage but doubles the damage of the next attack or ability that hits the victim (to a cap), and the projectile goes over walls, allowing her to make easy surprise attacks. If it hits nothing, it briefly becomes a puddle on the ground that induces the status to anything that walks into it, which is quite unique for a skillshot, and its cooldown resets on hitting a champion. Like any other champion with a hard CC on a basic ability (Lux, Morgana, Anivia, etc.), chasing her is an exercise in futility because of her E and her naturally high movement speed, but like Singed, it's also outright suicidal because the damage from her E+Q combo lets her destroy pursuers even faster than him. Lastly, her ult is a low cooldown blink that lets her teleport to a location for a second and teleport back, allowing her to dodge skillshots, make hit-and-run attacks with relative impunity, or just fake out opponents. This ultimately makes for a champ that is frustrating to fight because of her being so hard to punish due to having damage out the ass with the CC and mobility to complement it.

* Zoe. Her Q is a projectile that can be redirected much like Orianna's ball, with damage that scales with range and can ramp up to absolutely insane levels for a single ability, to the point that a capped Q can erase 40-50% of most lane opponents' health '''from level 1'''. Her W lets her use summoner spells and item casts recently used by other champions on demand, allowing her to use both her allies and her enemies' strengths against the latter. Her E is the first ability in the game to induce sleep, which is a combination slow and stun that is broken on damage but doubles the damage of the next attack or ability that hits the victim (to a cap), and the projectile goes over walls, allowing her to make easy surprise attacks. If it hits nothing, it briefly becomes a puddle on the ground that induces the status to anything that walks into it, which is quite unique for a skillshot, and has a low cooldown to boot. Like any other champion with a hard CC on a basic ability (Lux, Morgana, Anivia, etc.), chasing her is an exercise in futility because of her E and her naturally high movement speed, but like Singed, it's also outright suicidal because the damage from her E+Q combo lets her destroy pursuers even faster than him. Lastly, her ult is a low cooldown blink that lets her teleport to a location for a second and teleport back, allowing her to dodge skillshots, make hit-and-run attacks with relative impunity, or just fake out opponents. This ultimately makes for a champ that is frustrating to fight because of her being so hard to punish due to having damage out the ass with the CC and mobility to complement it.