Slay the Spire 2 Switches to the Godot Engine
Published 2024-04-13Updated 2026-09-193 min read
Mega Crit confirmed to IGN that Slay the Spire 2 dropped Unity for the open-source Godot engine — a decision made after Unity's per-download fee policy shook developer trust in 2024.
Days after the sequel's announcement, Mega Crit confirmed to IGN that Slay the Spire 2 runs on the open-source Godot engine — the team had abandoned Unity, the engine behind the original game.
The context was Unity's 2024 install-fee proposal, which proposed charging developers per game download and detonated developer trust across the industry. Whatever Unity's eventual walk-back, Mega Crit had already moved: the sequel was rebuilt on Godot, trading Unity's "modern features and expanding toolset" for an open-source pipeline the studio fully controlled.
The choice turned out to be quietly consequential:
- Modding — the open engine made the community's modding scene (ModTheSpire, BaseMod, the console) possible in Early Access.
- Portability — the game shipped with full Windows, macOS and Linux support (see system requirements).
- Transparency — as later coverage showed, the team's relaxed attitude toward the engine's open nature became part of the sequel's public identity.
At the time, the switch simply read as a vote of confidence in open source from one of indie gaming's most trusted studios. Two years and millions of sales later, it looks like one of the savviest engine calls of the generation.
Keep reading: