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Witcher 3: Wild Hunt – RemasteredMods and Steam Workshop
Slay the Spire 2 has had a built-in mod loader since launch and official Steam Workshop support since Major Update #2 (v0.107.1, Jun 19, 2026): subscribe on the Workshop and mods download to every device you play on. Modded progress is saved separately, co-op partners should run the same gameplay mods, and mods for the first game cannot work because the sequel uses a different engine.
Slay the Spire 2 supports mods through the Steam Workshop: since Major Update #2 (v0.107.1) on Jun 19, 2026, "you can browse and install mods directly from the workshop, and they will be automatically downloaded to all devices where you play on Steam" (Mega Crit's Major Update #2 notes). The game "has had an integrated mod loader from day one", Mega Crit engineer Ed Lu wrote, but until then the only supported way to install a mod was to download it and place it next to the game's executable, and Mega Crit "purposefully haven't been advertising mod support, as we knew it still needed some work" (Mega Crit's June 2026 Neowsletter). Mods made for Slay the Spire (2019) do not work: "Compatibility is impossible between sts1 and sts2 as it's a separate game engine," Casey Yano said (Mega Crit's March 2025 Neowsletter).
Quick facts
| Mod loader | Built in since launch, Mar 5, 2026 |
| Steam Workshop | Since v0.107.1, Jun 19, 2026 (Mega Crit) |
| Where | Slay the Spire 2 Workshop on Steam |
| Uploading | Mega Crit's sts2-mod-uploader tool |
| First-game mods | Not compatible: a separate engine (Mega Crit) |
| Saves | Modded progress kept apart from unmodded (Mega Crit) |
| Co-op | Everyone should run the same gameplay mods |
| Engine | Godot |
| Data sites Mega Crit named | Spire Codex, Spiracle (Mega Crit) |
How to install mods
Subscribe on the Workshop. Since Major Update #2 the Steam Workshop is "the official way to browse and install mods, right in the Steam client", and subscribed mods download automatically to every device where you play on Steam (Mega Crit's June 2026 Neowsletter). Before that, mods had to be downloaded from elsewhere and placed in your mods directory next to the executable, and that still works for mods not on the Workshop (Major Update #2).
The game asks before loading mods. A beta fix in v0.111.0 (Aug 14, 2026) refers to players who "declined mod loading, but left their mods installed" (v0.111.0 notes), and the main menu has a "mod settings" button with a Modding menu that works with a controller on the public beta since v0.108.0 (Jul 3, 2026) (v0.108.0 notes).
Workshop and local copies can both be installed. On the public beta since v0.108.0, "Steam mod now takes precedence over local if the version is greater" (v0.108.0 notes).
How mods are built and loaded
A mod is declared by a small JSON file. Mega Crit reworked the format in v0.99 (Mar 13, 2026, on the main branch Mar 17): every mod ships a "<mod_id>.json" manifest outside its PCK, the JSON is the only required file and says whether the mod includes a PCK or DLL, mods can declare dependencies, and the list of mods loaded last time is kept in settings.save, whose order is the load order (v0.99 notes; v0.99.1 notes). The same patch updated the bundled Harmony and MonoMod libraries for Apple Silicon Macs, so modders no longer had to replace them by hand.
The manifest's affects_gameplay field matters for co-op. If it is false, "the mod will not be checked against the host's mods in a multiplayer game" (v0.99 notes), so cosmetic mods do not block joining a friend.
Mega Crit publishes documentation for modders. Since Major Update #2 the XML documentation for the game's STS2.dll is published, and Mega Crit points new modders to "the community documentation" and asks for feedback in the #sts2-modding channel of its Discord or through the in-game F2 feedback tool (Major Update #2; June 2026 Neowsletter). On the public beta since v0.108.0, mods can register more than one assembly and load faster (v0.108.0 notes).
Modded saves and progress
Modded and unmodded progress are separate on purpose. Mega Crit explained in July 2026 that "unmodded saves are saved separately from your modded ones as a protective measure", which made a first modded launch look as if progress had been wiped; on the public beta since v0.108.0 your unmodded saves are copied into the modded save folder on that first launch, with a popup explaining it (v0.108.0 notes). Mega Crit said these changes would "come to the main branch soon", but no main-branch update has followed as of Oct 26, 2026.
Removing a mod no longer erases its progress. Since Major Update #2, "The base game no longer deletes progress from mods that are removed or errored", and loading a saved run with a modded character into the unmodded game shows an error instead of a black screen (Major Update #2). PCGamesN lists a mod, Unified Save Path, that shares unlocks between modded and unmodded saves (PCGamesN). See Unlocks and the Timeline.
Mods in co-op
Co-op partners should run the same mods. Mega Crit: "we still recommend having the same exact mods enabled as your teammates, particularly if they actually affect gameplay and are not merely cosmetic" (v0.108.0 notes). The public beta's v0.108.0 fixed many "version mismatch" errors between players with the same mods, crediting OLC of RitsuLib, and added more detailed error popups; since v0.110.0 the "Report Bug" button is hidden when any player in a session has mods (v0.110.0 notes). See Co-op Multiplayer.
Why first-game mods do not work
Slay the Spire 2 runs on a different engine from the first game. Mega Crit began the sequel in Unity and moved it to Godot after Unity's 2023 Runtime Fee (GameFromScratch, Apr 11, 2024), and when asked whether first-game Workshop mods would carry over, Yano answered: "Compatibility is impossible between sts1 and sts2 as it's a separate game engine. Sorry!" (Mega Crit's March 2025 Neowsletter). Popular first-game mods have to be rebuilt for the sequel; see Differences from Slay the Spire and Development History.
Mega Crit's view of modding is hands-off. Asked in August 2025 about expanding modding, Yano said "We're creating more entry points in the game", adding that in the first game "you can rewrite any part of the game already. You could put a game in the game or order a pizza already" (Mega Crit's August 2025 Neowsletter). Mod content does not go into the base game: "Making content is one of the parts of making video games. I'm not sure why we would ever add content from a mod" (Mega Crit's May 2025 Neowsletter).
Mods the press has covered
PCGamesN keeps a list of the best mods. Its picks (Christian Vaz, updated May 6, 2026) are:
| Mod | Author | What it does |
|---|---|---|
| The Watcher | lamali | Adds the first game's missing character, with her stances |
| Infinite Mode | KYL3R | Chapters of three acts at rising Ascension |
| BetterSpire2 | JDR | An incoming-damage counter and other quality-of-life changes |
| Blight | Tongs | A harder challenge |
| Damage Meter | PiPiFanDev | 17 multiplayer statistics |
| Undo and Redo | Jiesi Luo | Undo moves (not in multiplayer) |
| Act 4 Placeholder | iKenster | A stand-in fourth act |
| Slay With Controller | Caelus | Controller changes |
| Remove Multiplayer Player Limit | Rain_G | Up to 16 players, with no difficulty scaling |
| Unified Save Path | Jiesi Luo | Shares unlocks between modded and unmodded saves |
| AI Teammate | Sally | Up to three bot party members |
Source: PCGamesN, read Oct 26, 2026.
A PvP mod arrived within weeks of launch. Rock Paper Shotgun's Edwin Evans-Thirlwell reported SlayThePlayer by Maimun, in which two players start a co-op run on the same seed, climb separate maps and fight each other at every act boss, best of three acts (Rock Paper Shotgun, Mar 25, 2026).
Community tools
Mega Crit has pointed players to two data sites. Its May 2026 Neowsletter named Spire Codex and Spiracle as "community projects that collect their own stats and provide data, tools, guides, etc. for players" (Mega Crit's May 2026 Neowsletter). Spire Codex reads its card, relic and Epoch data from the game's files, and this viki cites it for exact card text; see Cards.
Frequently asked questions
Does Slay the Spire 2 support mods? Yes: Slay the Spire 2 has had a built-in mod loader since launch and official Steam Workshop support since v0.107.1 on Jun 19, 2026. Subscribed mods download automatically to every device you play on.
How do you install Slay the Spire 2 mods? Subscribe to a mod on Slay the Spire 2's Steam Workshop page and launch the game, which asks whether to load mods. Mods from elsewhere can still be placed by hand in the mods folder next to the executable.
Do Slay the Spire 1 mods work in Slay the Spire 2? No: Casey Yano said "Compatibility is impossible between sts1 and sts2 as it's a separate game engine." Slay the Spire 2 is built in Godot.
Do mods delete my Slay the Spire 2 progress? No: Slay the Spire 2 keeps modded and unmodded saves apart, and since v0.107.1 it no longer deletes progress from removed or broken mods. On the public beta, your unmodded save is copied over on the first modded launch.
Can you use mods in Slay the Spire 2 co-op? Yes: Mega Crit recommends that all players run "the same exact mods", particularly mods that affect gameplay. Cosmetic mods that declare they do not affect gameplay are not checked against the host's.
Is there a Watcher mod for Slay the Spire 2? Yes: PCGamesN's list of mods includes The Watcher by lamali, which adds the first game's fourth character with her stances. The Watcher is not in Slay the Spire 2 itself.
What are the best Slay the Spire 2 mods? PCGamesN's list (updated May 6, 2026) picks The Watcher, Infinite Mode, BetterSpire2, Blight and Damage Meter among others; there is no official ranking.
Sources
- Slay the Spire 2’s Next Big Major Patch - Explained in 9 Minutes, MidMillennial, Jun 19, 2026 (video)
- FIFTEEN new OP multiplayer cards?? | Spire 2 Patch Rundown V0.108.0, JapaneseExport, Jul 3, 2026 (video)
- Slay the Spire 2: Q&A with Anthony & Dani of Mega Crit, Manifest Conference, Jul 10, 2026 (video)
- Major Update #2 - v0.107.1, Mega Crit (Ed Lu), Jun 19, 2026
- The Neowsletter - June 2026, Mega Crit (Ed Lu), Jun 20, 2026
- The Neowsletter - March 2025, Mega Crit (Casey Yano), Mar 12, 2025
- The Neowsletter - May 2025, Mega Crit (Casey Yano), May 15, 2025
- The Neowsletter - August 2025, Mega Crit (Casey Yano), Aug 14, 2025
- Beta Patch Notes - v0.99, Mega Crit, Mar 13, 2026
- Patch Notes - v0.99.1, Mega Crit, Mar 17, 2026
- The Neowsletter - May 2026, Mega Crit (Demi Montes), May 23, 2026
- Beta Patch Notes - v0.108.0, Mega Crit, Jul 3, 2026
- Beta Patch Notes - v0.110.0, Mega Crit, Jul 31, 2026
- Beta Patch Notes - v0.111.0, Mega Crit, Aug 14, 2026
- Slay the Spire 2 Workshop, Valve (Steam Community), read Oct 26, 2026
- sts2-mod-uploader, Mega Crit (GitHub), read Oct 26, 2026
- Best Slay the Spire 2 mods, PCGamesN (Christian Vaz), updated May 6, 2026
- This Slay The Spire 2 PvP mod lets you battle friends mid-run to see who's made the better deck, Rock Paper Shotgun (Edwin Evans-Thirlwell), Mar 25, 2026
- Smash Indie Hit Sequel Slay the Spire 2 Made with Godot, GameFromScratch, Apr 11, 2024
Moments
Slay the Spire 2’s Next Big Major Patch - Explained in 9 Minutes
MidMillennial
FIFTEEN new OP multiplayer cards?? | Spire 2 Patch Rundown V0.108.0
JapaneseExport
Slay the Spire 2: Q&A with Anthony & Dani of Mega Crit
Manifest Conference
Related
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Colorless CardsSlay the Spire 2 has 64 Colorless cards on its main branch (v0.107.1), 39 Uncommon and 25 Rare, that any character can use; 11 of them appear only in co-op. You get them from the Merchant (2 a visit), Neow's Lead Paperweight, events, relics such as Dingy Rug and Toolbox, and cards that create them, such as Jack of All Trades and the Regent's.
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Curses, Statuses and Quest CardsSlay the Spire 2 has 18 curses, 16 statuses and 3 Quest cards on its main branch (v0.107.1). Curses stay in your deck until removed (Eternal ones, such as Ascender's Bane from Ascension 5, never leave), statuses last one combat, and Quest cards (Byrdonis Egg, Lantern Key, Spoils Map) pay out when you finish their task.
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Defect CardsThe Defect has 88 cards in Slay the Spire 2's main branch (v0.107.1): 4 Basic, 20 Common, 36 Uncommon, 26 Rare and 2 Ancient, two of them multiplayer only. This page lists every one with its cost, effect, upgrade and patch changes, and the key cards guides name for Orbs, Status and Claw.
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Ironclad CardsThe Ironclad has 87 cards in Slay the Spire 2's main-branch game data (v0.107.1): 3 Basic, 20 Common, 36 Uncommon, 26 Rare and 2 Ancient, two of them for multiplayer only. This page lists every one with its cost, effect, upgrade and patch changes.
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Multiplayer CardsSlay the Spire 2 has 21 multiplayer-only cards on the main branch v0.107.1, two for each character and 11 colorless, such as Knockdown, Flanking and Rally, which only appear in co-op runs and target allies. The opt-in public beta adds 16 more (15 in v0.108.0 and Tutor in v0.109.0).
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Necrobinder CardsThe Necrobinder has 88 cards in Slay the Spire 2's main-branch game data (v0.107.1): 4 Basic, 20 Common, 36 Uncommon, 26 Rare and 2 Ancient, 2 of them for multiplayer only. They build around Osty and Summon, Doom, Souls and Ethereal cards.
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Regent CardsThe Regent has 88 cards in Slay the Spire 2's main-branch game data (v0.107.1): 4 Basic, 20 Common, 36 Uncommon, 26 Rare and 2 Ancient, 2 of them for multiplayer only. Many cost Stars as well as Energy, and Forge cards build the Sovereign Blade.
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Silent CardsThe Silent has 88 cards in Slay the Spire 2's main-branch game data (v0.107.1): 4 Basic, 20 Common, 36 Uncommon, 26 Rare and 2 Ancient, two of them for multiplayer only. This page lists every one with its cost, effect, upgrade and patch changes.
See also
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Unlocks and the TimelineSlay the Spire 2 unlocks its characters in a chain by playing one run (win or lose) with each: the Ironclad unlocks the Silent, then the Regent, the Necrobinder and the Defect. Everything else (cards, relics, potions, Ancients, the Underdocks, Ascension, Daily and Custom runs) comes from 57 Epochs on the Timeline, earned by goals such as beating an act or by spending score; Daily and Custom runs earn none.
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Differences from Slay the SpireSlay the Spire 2 keeps the first game's card combat and map but replaces boss relics with Ancients, adds enchantments, afflictions, Quest cards, an alternate Act 1 and up to 4-player online co-op, swaps the Watcher for two new characters (the Regent and the Necrobinder), and has 10 Ascension levels instead of 20. It is still in Early Access, with no true ending yet.
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Development HistorySlay the Spire 2 is made by Mega Crit, the studio of Casey Yano and Anthony Giovannetti, which began it around May 2021 in Unity and moved it to the Godot engine after Unity's Runtime Fee in September 2023. Art director Marlowe Dobbe led a brighter, more animated look, and Mega Crit announced the game in April 2024, delayed it once and launched it in Early Access on Mar 5, 2026.
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CardsSlay the Spire 2's game data holds 577 cards on the main branch (v0.107.1): about 88 for each of the five characters, 64 Colorless, 18 curses, 16 statuses, 3 Quest cards, and Event, Ancient and Token cards. Cards are Attacks, Skills, Powers, Statuses, Curses or Quests; rarities run Basic, Common, Uncommon, Rare and Ancient; card rewards offer 3 cards and you take 1.
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Daily Climb and Custom ModeBesides Standard runs, Slay the Spire 2 has Daily runs, one shared run a day with a fixed character, Ascension and three modifiers, ranked on a friends-only leaderboard, and Custom runs, where you pick from 16 modifiers such as Draft, Flight, Midas or Murderous. Neither earns Epochs. Phobia Mode is a setting that redraws creepy enemies; Mega Crit is working on new experimental modes, none released yet.