Slay the Spire 2 has pushed its second major main-branch update, moving months of beta testing into the build everyone plays. Update 0.107.1 adds full Steam Workshop mod support, replaces the Doormaker boss with Aeonglass, introduces a first-pass Bestiary, and corrects a long-standing problem with how the game generated random numbers. The headline takeaway is simple. The game feels a bit tougher in places, but its randomness is now fairer.
Quick answer: Update 0.107.1 is live on the main branch. To use mods, subscribe through the Slay the Spire 2 Steam Workshop and they load automatically through the game’s built-in mod loader. Expect Aeonglass as a new boss, a Bestiary screen, reworked RNG, and a large batch of card and relic balance changes.
Steam Workshop mod support is now available
The biggest brand-new addition is the Slay the Spire 2 Steam Workshop. Mega Crit built the game with modding in mind and shipped an integrated mod loader from day one, but it held back on advertising the feature until it was ready. With Workshop now open, you can browse and install mods directly from Steam with a single click, and the game handles loading them for you.
The catalogue is small at launch and will grow over time. To get started, open the game’s Steam page and use the Workshop tab to subscribe to anything you want.
RNG rework fixes correlated randomness
A community investigation revealed that the game’s number generation was producing outcomes that were too predictable. The problems ranged from chance rolls that shifted depending on the region you were in, to specific cards that could not appear in the build at all. Players who complained about receiving Debt too often from Neow’s Bones were, as it turns out, correct.
Programmer Ed Lu confirmed the studio had real RNG problems and rebuilt the system. The new implementation is described as evenly distributed with no human-detectable correlation. In practical terms, draws, rewards, and chance effects should now feel genuinely random rather than quietly skewed.
Doormaker removed, Aeonglass added
The Doormaker boss has been cut. Co-Founder Casey Yano said the fight landed over the complexity threshold the studio wants for the game. Taking its place is Aeonglass.
Aeonglass works by feeding you Wither cards. If a Wither card is still in your hand at the end of your turn, it deals damage, and those cards become more punishing as the fight drags on. The lesson is to close the fight quickly rather than letting it stall.
Infested Prism and other enemy reworks
Infested Prism is one of the more dangerous reworked encounters. It makes your skill cards ‘tainted’, and each tainted skill you play increases the damage you take from attacks. The counterplay is to be aggressive and push for a fast kill, similar to how veterans of the first game handled the Gremlin Nob.
Several other enemies received adjustments during the beta period that have now reached the main branch, including changes to Skulking Colony. The overall effect is that more fights demand specific counterplay instead of a single repeatable strategy.
The Bestiary tracks every creature
The update introduces the Bestiary, a long-requested feature that collects data on the creatures you encounter. In this first form it lists models, moves, and animations. Yano noted that the studio skipped this feature in the original game because there was no good way to frame an overarching story, but the world of Slay the Spire 2 has more narrative room. Detailed stats and lore are planned for later.
Balance changes and accessibility goals
The update carries a large batch of class balance adjustments, plus new artwork, audio, and writing. Some relics available from start-of-act Ancients have changed as well. Mega Crit has acknowledged the game is quite hard right now and wants the lower Ascension levels to be more accessible to a wider range of players, while keeping a deep challenge intact at the top end.
Part of that tuning aims to move the game away from relying on broken infinite combos. Many weak cards and relics were buffed in the same pass, so the net result is not simply harder across the board. Because so much has shifted, it is worth reading every card and relic you come across rather than leaning on old knowledge.
| Change | What it does |
|---|---|
| Steam Workshop | One-click mod browsing and installation through Steam, loaded automatically |
| RNG rework | Evenly distributed randomness with no detectable correlation |
| Aeonglass boss | Replaces Doormaker; hands out Wither cards that hurt at end of turn |
| Infested Prism | Taints skill cards so each one raises the attack damage you take |
| Bestiary | First-pass creature log of models, moves, and animations |
| Balance pass | Class adjustments, relic tweaks, card buffs, and a fairer low-Ascension curve |
How to confirm the update is installed
You are on the right version when the main menu reports update 0.107.1 and the Bestiary is accessible in-game. If you previously opted into the beta branch, switch back to the default branch in Steam to receive the same content as everyone else. With Workshop live, any mods you subscribe to should appear without manual file copying.
Mega Crit is expected to return to beta patches in the coming weeks as it tests new ideas, so the main branch should stay stable for a while. That gives you time to learn the current state of the game, and the door is now open to reshape other parts of it through mods.
