I want to be completely honest with you before we go any further. I have sunk hundreds and hundreds of hours into Slay the Spire, Monster Train, and basically every roguelike card game you can imagine. So when MegaCrit dangled a sequel in front of me, powered by Yorkshire Gold and a crippling addiction to video games, I did not stop playing from the moment it released. The result? I found exploits. Many of them. And I am going to walk you through every single one.
For the American audience: the title is sarcasm.
What You're Actually Playing, And Why It Already Has Cracks
For anyone new to the series, Slay the Spire 2 is a roguelike deck-building game. Similar to its predecessor, you select a character, play cards to defeat monsters, gain new cards, and complete encounters as you travel through multiple levels of the titular Spire. The game reached early access on March 5, 2026, for Linux, macOS, and Windows. MegaCrit stated the early access version is mostly feature complete, using placeholder art for some of the newer cards and items, and expects most of the early access period to be used to balance the game.
Balance. That word is doing a lot of heavy lifting.
On its first day in early access, Slay the Spire 2 reached over 177,000 concurrent players on Steam, and MegaCrit confirmed that sales within the first week exceeded 3 million copies. By March 8, the game had already peaked at 574,638 concurrent players, making it the most-played roguelike in Steam history. The world fell in love with it. And I immediately started looking for the cracks.
Because of the roguelike nature with numerous systems affected by random elements, most roguelike deck-building games require intensive playtesting to make sure the game is properly balanced. Early access means that playtesting is ongoing. Which means the window for breaking things is wide open. Think of me like a truffle pig looking for exploits.
The First Exploit: Mass Card Transformation on Floor One
The run begins with a relic choice from the six-eyed whale Meow. I chose New Leaf, which normally transforms one card into another: make a Strike into a Defence, or if you're lucky, something rare. Useful, but not game-breaking. Not yet.
Here is where things go sideways almost immediately. By navigating the on-screen menus with the up arrow key followed by a few left arrows, I can get back to the card choices in the background of the UI. I can then highlight the other cards by pressing Enter, which selects them. I keep doing this until every card except the first one has a glowing blue border. The game now believes all ten cards have been selected for transformation. Then I press confirm.
My entire base starting deck disappears into the abyss and gets replaced with a fresh hand of random cards. The roll is not guaranteed, but I landed three rare cards and several powerful skills, including my immediate favourite: Capture Spirit. The devs are already weeping. I have not even left floor one.
Because the player cannot predict which cards will be presented as rewards, they must build their deck on the fly, trying to develop potential combinations and synergies between cards and other gameplay elements, while at the same time avoiding diluting their deck with cards that do not work well together. I skipped that part entirely.
Why I Chose Ascension One, And Why That Decision Is Smarter Than It Looks
I played this run on Ascension One difficulty. Most people hear that and assume it makes the game harder. In a technical sense, it does. But the specific modifier Ascension One applies is an increase in elite enemy spawns, and that is precisely what I want.
Elites are difficult enemies. They are hard to defeat in a standard run. But they drop relics upon death, and relics are passive buffs, curses, or boosts that remain active for the entire run. The earlier I can start collecting relics, the earlier I start scaling my power in ways the game was not designed to handle on floor one. So paradoxically, Ascension One is actually easier for someone who understands how to farm elites aggressively. I have unlocked a wide library of relics and cards through previous playthroughs, which makes the pool of potential rewards significantly more interesting.
Up to 20 Ascension difficulty levels unlock with each successfully completed run, each adding a cumulative negative effect such as lower health or stronger enemy attacks. Ascension One adds just enough difficulty to generate more elite rewards without actually threatening my build at the stage I am planning to break the game.
Meeting the Necrobinder: The Character Built for Infinite Loops
The character I am playing is the Necrobinder, one of the two brand-new characters introduced in Slay the Spire 2. The Necrobinder is a sassy lich who was once part of the Spire's forgotten history. She is a fragile but tactically dense spellcaster who relies on a massive, reanimated skeletal hand named Osty to do her dirty work. Unlike any character in the original game, she effectively functions as a duo-unit, managing both her own limited resources and her companion's physical presence.
She starts with 66 Max HP, the lowest of any character. That sounds like a disadvantage. In practice, Osty absorbs incoming damage before it reaches her, which means her actual survivability is much higher than her health pool implies. By utilising the Summon mechanic efficiently, you can bolster Osty during combat, effectively letting you stack an endless supply of health, and since it is not Block, it does not wear off.
But the mechanic that truly matters for what I am building is the Soul card system. Souls are colourless, zero-energy cards that draw two cards when played and carry the Exhausted status effect. This means, once they are used, the Souls are gone for good. Zero energy. Free card draw. Those two words together are the exact combination that leads to infinite builds. With enough Souls cycling through my hand and a small enough deck, I can draw every single card I own in a single turn, giving me theoretically unlimited plays.
The Campfire Upgrade Exploit: Saying Goodbye to Game Balance
After working through the early combats using Infeebling Touch to negate all incoming damage and Capture Spirit to generate Soul cards, I arrived at the first rest site. Normally, a campfire lets you either recover lost health or upgrade a single card in your deck. One card. That is what the developers intended.
I selected all the cards in my deck. When I pressed confirm, the game upgraded every one of them.
This is only remotely possible because of an input quirk similar to the arrow key exploit used earlier. The game does not cap the selection at one card in every context. By selecting the lot and hitting the tick button, I sent every card in my deck through the upgrade process simultaneously. Infeebling Touch became more powerful. Capture Spirit Plus now generates more Souls. The entire deck is now operating at upgraded quality on floor one, which the developers absolutely did not intend.
As MegaCrit's Anthony Giovannetti once described an earlier broken card interaction in the original game: "It was totally broken. You could copy skills and go infinite really easily. Going infinite is the number one thing we try to make really rare. It makes the actual playing of the game trivial." I respect that philosophy. I am also completely ignoring it.
Poke: The Weakest Card in the Game, Which Is About to Destroy Everything
At a certain point I picked up a card called Poke. It is a zero-mana card that does a trivial amount of damage. Most experienced players would not even consider adding it to a serious run. I took it immediately.
Here is why. Poke costs nothing to play. That means in a deck cycling on Soul cards, I can play Poke every time it appears in my hand without spending any energy. On its own, that makes it an occasional, mildly satisfying tap on an enemy's shoulder. But later, at a shop, I found the Punch Dagger relic. Upon pickup, it lets me enchant a card with Momentum Five. Every time that card is played, it increases its own damage by five for the rest of the combat. I attached Momentum Five to Poke.
Now every cycle of my Soul chain that pulls Poke into my hand adds five more damage to every subsequent Poke. The damage compounds. A card that started doing two or three damage is now, by the tenth cycle, doing over fifty. The weakest card in my deck became the centrepiece of a scaling damage engine that the enemies have absolutely no answer to.
A further aspect of roguelike deck-builders is balancing the size of one's deck, passing up rewards or using removal tools to keep the deck lean and its outcomes more predictable. I followed this principle religiously, but not for predictability. I thinned my deck so that Poke would appear as often as possible per cycle. The less cards, the more Poke. The more Poke, the more damage. The more damage, the faster I become an undefeatable god.
Deck Thinning as a Philosophy: Skip Everything, Delete the Afterlife
Most players feel compelled to take every card reward. After every combat, there are three cards on offer, and convention says you should pick one. I skipped nearly all of them after the early game.
This is a deliberate and counterintuitive strategy. The more cards I add to my deck, the harder it is to draw into my key pieces: Capture Spirit, Poke, and later Borrowed Time. A bloated deck slows the cycle down and introduces dead draws at the worst possible moments. So I not only skipped card rewards, I actively sought ways to remove cards I no longer needed.
I found the Dusty Grimoire at a shop: a one-cost card with no active combat effect that removes one card from my deck at the end of each fight. I routed my path specifically to pass through it. When the Fie Hopper enemy stole one of my cards during combat, I looked at what it took, realised I did not need it, and left it on its corpse. In one combat I removed two useless cards from my deck without spending any resources to do so.
I deleted the card called Afterlife. I, the Spiffing Brit, removed the afterlife from the game. You're welcome.
By the third floor, my deck contained seven cards. A key aspect of roguelike deck-builders is balancing the size of one's deck, using removal tools to keep it lean and outcomes more predictable. In my case, predictable means: Poke kills everything before it gets a turn.
The Neurosurge Problem: Running on Borrowed Time
Neurosurge is a card that gains energy, draws cards, and applies Doom. The critical detail is that it costs zero energy to play. A free card that generates more energy and draws more cards is already an absurd value proposition. But it applies Doom to me, meaning I am on a countdown to dying from my own mechanic.
The Necrobinder's Doom mechanic is a unique death-mark system. When applied to enemies it executes them once their HP falls at or below their Doom stacks. When applied to me, Doom means I lose health at the end of my turn if I have not killed the enemy first. This sounds terrifying. In practice, since I never end my turn until the enemy is dead, it is functionally irrelevant.
The final piece of the puzzle arrived in one of the last rooms before the final boss: Borrowed Time. It applies Doom and gives energy, for zero energy cost. Free energy. That is the card that closes the loop completely. With Capture Spirit, Borrowed Time, and Poke, each full cycle through my deck generates more energy than it consumes. I gain net-positive mana every time the loop completes. The loop becomes truly, mechanically infinite.
Turn Zero: How I Killed the Final Boss Without It Ever Moving
Floor thirty-three. The final boss. I have seven cards in my deck. I draw all of them on the first round of combat. Four of them are exhaust cards, so I play them out immediately. That leaves me with three cards that matter: Capture Spirit, Borrowed Time, and Poke.
Capture Spirit hits the boss and generates four Soul cards in my draw pile. Neurosurge draws those Souls, which draw other Souls, which eventually draw Capture Spirit again. Each loop of this cycle costs one mana and generates one Soul more than it started with. Borrowed Time covers the energy cost and then some. The net result is that every completed loop leaves me with slightly more energy than I began with, while Poke's damage climbs by five with each appearance.
I never click the button to end my turn. The boss never moves. By the time Poke hits 54 damage per play and I have been cycling for several minutes, the Insatiable collapses before it has had a single turn. The final boss, one of the most terrifying enemies in the game, died to a card called Poke.
For the actual final encounter, the Door Maker, the loop extended further. I used the Touch of Insanity potion to make Capture Spirit completely free, removing even the one-mana cost from the cycle. At that point, the loop generates pure free energy with every rotation, Poke climbs to 96 damage per hit, and with the Vulnerable debuff applied, each swing connects for over 100. Six cards in my deck. Three that matter. One run done.
What This Actually Reveals About Early Access Roguelikes
I do genuinely love this game. I am not breaking it out of contempt. I am breaking it because I have hundreds of hours in the original and I approach every system the same way: as a set of rules waiting to be bent until they snap.
MegaCrit expects most of the early access period to be focused on balancing the game. That is honest and admirable. The original Slay the Spire went through the same process, and MegaCrit's data-driven approach to patching is well-documented. "If we make a mistake, we're releasing weekly patches," Giovannetti said of the original game's early access. "Because things are in flux, players can expect that the balance will change."
By April 2024, over 850 games on Steam were tagged as roguelike deck-builders, showing significant growth in this genre. Every one of those games has players like me prodding at the seams. The most successful ones patch quickly, listen to the community, and use exploit discoveries as a design signal rather than a catastrophe.
Slay the Spire 2 will be fine. It will be patched. The arrow key exploit will close. The campfire upgrade trick will be capped. The Poke momentum build will probably be adjusted. And then someone will find the next thing.
Quickly, before they patch it: go find out what you can break. Let me know in the comments how it goes. I'll see you in the next one. Have a wonderful day and goodbye for now.