Game Breaker / The Witcher

• The Witcher: Game of Imagination

The Witcher

• The Igni Sign starts off as relatively subpar (very high endurance cost, very low damage). However, if leveled properly, it can become so ludicrously powerful that even bosses become ridiculously easy. Combined with the Tawny Owl potion's ridiculous speed of endurance regeneration, near the end of the game you can simply use just that.
• The Aard as well, especially early on. Most humanoid enemies and dogs (including the first act boss) can be knocked over and one-shot-killed with just the basic version.

The Witcher 2: Assassins of Kings

• The Quen sign. It throws back enemies that hit you, rendering most combat laughably simple. Combined with the right equipment, it can absorb all damage at level 2, and even earlier it makes most of the game a cakewalk. Even the final boss is not immune. Quen got nerfed quite a bit in the 1.3 update.
• The ability to riposte during swordfights. Can be acquired as soon as the three main skill trees open, with the cost of a measly skill point. Before getting it, you're likely to spend more time dodging blows than dealing them. After you take this one, the combat dynamics change so drastically that almost every standard armed encounter turns into a cakewalk. It's actually quite ironic that it becomes available not long after the player has likely learnt how not to suck in combat without it.
• Bombs. You can make a load of them and just chuck them out like candies. Works especially well on bosses, even better if you brought the skill that multiplies the damage dealt by 100%, and it can be taken even further with a special torso armor. The fact that the basic (Grapeshot) requires just two most common alchemy ingredients, has a good range and damage plus can hit a lot of targets at once just further drives the point home.
• Heck, Igni still counts too, you just have to invest in it. With maxed spell damage enhancements and skills, hammering the sign key to machine gun out fireballs will rapidly drain the health of anything not immune to fire. If your enemy is one of the few which is fireproof, blast em' anyway- a single blast from Igni will force them into a few seconds of flinch animation, dropping their guard.
• Combat Acumen is basically an instant kill button against any non-boss character, provided the gauge is full. That includes many of the tougher monsters that normally take a lot of damage to kill.
• Going full alchemy turns you into an unstoppable megatank. A big part of this is the "Catalysis" skill, which boosts potions and most importantly reduces negative effects, making risky recipes like White Raffard's Decoction (vitality +50%, damage -30%) game-breakingly powerful (vitality +82%, damage unchanged). Combine this with an armour and resistance-boosting potion, and the only way to die is if you're actively trying to do so.

The Witcher 3: Wild Hunt

Main Game

• The decoctions, special potions with long lasting effects, can result in extremely overpowered gameplay. With Acquired Tolerance and Heightened Tolerance, you can use without drawback three of them at the same time in the base game and four with Blood and Wine. These skills are Magikarp Power however so it will take some time to be effective.
  • The Ekhidna Decoction, which gives you health every time you expend your stamina. In result, with high stamina regen build, spamming the Quen sign allows you to regain any health the sign didn't absorb, making healing potions superfluous and providing means to heal yourself infinitely through combat with minimal risk.
  • The Arachas Decoction, despite its description actually give the most damage resistance to heavy armor which already has sky high resistance and armor, turning your Ursine Geralt into an Iron Jugglenaut.
  • The Ekimara Decoction heal with every hits, work extremely well with Whirl, easily top up your health for...
  • The Water Hag Decoction increase your attacks by a whoping 50% if you can maintain your max health which you can easily do with the two decoctions above. And again, by the middle of the base game you can and should drink three decoctions.
• Quen can make you functionally invulnerable even on the highest difficulty. Its normal effect is a resistance% based shield that makes you Immune to Flinching and grants Contractual Boss Immunity to most status effects as well as removing those status effects when cast. The alternate is a completely impenetrable bubble shield that heals you when it gets hit and (if fully upgraded) returns some of that damage to the enemy. Quen essentially turns you into The Juggernaut. To balance this, Quen is on a short timer - 30 second and without the proper build, it can only take a single hit. It also provided no resistance against knockback.
• Axii is arguably the most overpowered sign of all, despite the story limitations. Fully powered it prevent enemies from even attempting to approach you during the casting, hits two targets, turns enemies against their allies while giving them a huge damage buff, and even if it actually fails it still staggers the targets. On top of this it has a bunch of Jedi Mind Trick uses in dialog.
  • Interestingly, the overpowered nature of the sign is defied with the use of Axii in a story context. Geralt can, at one point, explain to Lambert why the sign can only be used at certain spots outside of combat: it's a temptation that needs to be avoided. That's right - the character you follow decided it's morally wrong for you to have the game too easy.
    Geralt: [Axii] tempts you to overuse it. Force a merchant to reduce his price. Make an arrogant noble drink from a gutter. Teach someone to show you respect. That can become hard to resist.
• As far as skills go Gourmand takes the cake for single-handedly breaking the healing game by increasing the duration of all food and drink to twenty real-life minutes uninterrupted by damage or combat. That's right; Geralt learns to appreciate his food to such an extent that a drink of water can heal him four or five times over. Granted, the rate of regeneration is nothing spectacular and it does tend to fall off with higher levels, but it still makes the early game a breeze.
• Deliberately invoked during the final portion of the game, as Ciri demonstrates precisely how powerful she is. In her playable section in the finale, she has a larger health bar, can one-shot all enemies regardless of level, and instantly teleport across the battlefield to the nearest foe.
• You'll be hard-pressed to find a Mutation in Blood and Wine that isn't ridiculously overpowered. Probably the best among them is Euphoria, which adds a flat increase in sword damage and sign intensity for every point of toxicity Geralt accumulates. Combining this with a mixture of already game-breaking potions and decoctions will turn Geralt into a nigh invincible whirling dervish of death.
• The Whirl skill is reasonably powerful on its own, albeit limited by the defensive capabilities of enemies, humans in particular. However, upgrading a sword with the Severance word of power in the Hearts Of Stone expansion not only extends its range, but also negates blocking to a ridiculous extent (at lower than Death March difficulty). This allows Geralt to carve up groups of enemies with ease, turning most encounters with bandits into a complete joke. It's essentially Geralt's Omnislash. The developers must have realized it too, because one of the main reasons that Alps and Bruxae in Blood And Wine are so difficult to fight is because they don't stay still long enough for this trick to work. Even in the Hearts Of Stone expansion that makes it even stronger makes efforts to combat against it, as Olgierd straight up No Sells the move by deflecting every single hit, and The Caretaker's lack of hitstun means that making the mistake of trying it on him will typically immediately end in you taking a big hit for your trouble, and him likely regaining all the health you took from him with that hit alone.

Gwent

• Single Cards:
  • The Mysterious Elf card can only be won from a Skellige hermit druid named Gremist after a long sidequest but it is well worth the effort to unlock. As a Spy card with zero power and Hero status it basically serves as a free two cards during whichever round it is played, in other words... a Gwent version of the infamous Pot of Greed in a game where decks typically consist of less than thirty cards. This makes it insanely easy for the player to access their better cards and turn the tide of battle, making this arguably the strongest single card in the game.
  • Cirilla Fiona Elen Riannon and Geralt of Rivia adds the story's two main protagonists to the game and they are just as broken as expected. Boosting 15 power each and an immunity to other card effects thanks to their Hero status they can single-handily change the flow of a round and force an opponent to break out their best cards to counter them. Nether has any special powers, but with raw strength and reliability they can make any deck stronger regardless of strategy or tactics. One is a juggernaut, two is typically a game over for whatever poor sod faces them.
  • The Decoy card can be a bit tricky to time right, but has unparalleled effectiveness in the hands of a master. It's effect is simple but powerful, returning a card on the player's field to their hand. Normally, this is merely used to trick an opponent into dropping their best cards before reclaiming a powerful unit, but it has more versatile uses as well. Because it captures any card on the players side of the field it can be used to snatch up enemy spies to use against the opponent, and to repeatedly reuse extremely powerful unit drop abilities such as Medic to return multiple units into play (and then get another trigger of THOSE card's abilities), or Scorch units such as Villetretenmerth to repeatedly wipe enemy threats. This one single card can set up chains to trigger multiple other cards and generate some pretty insane combos in skillful hands and completely break the game when played at the right moment.
  • Scorch is basically the Blue Shell of Gwent. It nukes the strongest card on the field when played, including any cards that are tied for strongest. This allows the player who played it to gain a sizable advantage at worst and outright cripple their opponent at best. Not only does the victim lose their strongest card, they might have just lost half their entire units if they weren't careful about maintaining a diverse set of power levels. This is especially deadly against Monster decks since many swarm cards have similar levels of strength. Nothing worse than bringing out your army and seeing it become barbecue in the span of a single turn.
• Strategies:
  • Spy Spam, full stop. Gwent is a game of limited resources and careful planning so what better way to break it than through sheer brute force tactics and resource denial? Spies are supposedly balanced by trading one strong card to the opponent in exchange for drawing two fresh ones, only there's a massive power discrepancy between the Spies power and the usefulness of their effect. Trading one card for two is already a pretty good deal on its own but with multiple Spies the ability becomes completely broken beyond all repair. Because players must play a card each turn or pass it becomes easy to force an opponent to throw away half their hand while the player increases theirs with each Spy played. The end result? By round two, one player has over a dozen cards in hand while their opponent is lucky to have half that. Needless to say, a Curbstomp Battle usually follows right after.
  • If Spy Spam is bad, combining them with medic and scorch is the end-all-be-all at the highest difficulty. At that level, all decks have multiple Scorchs and Decoys and Villentretenmerth to recycle your spies and burn off your powerful Tight Bond units. The solution? Multiple medics and Scorchs. Powerful cards are scorched off the table? Revive them with medics. Your spies are decoyed away? Revive them with medics the next turn. Better yet, scorch them off your table and revive them that turn. The worst part is that there's an NPC, Sasha, who uses the exact same strategy but better ^note She also has Emhyr var Emreis: The Relentless Leader card which allow resurrection of a card in your opponent's discard pile and she was That One Boss of base game's Gwent.

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