Per the README (in Chinese) it covers map generation, Neow and the other Ancients, combat, elites and bosses, events, shops, rest sites, chests, rewards, potions, relics and enchantments. RNG streams can be copied exactly or reseeded, which suits search with or without known randomness. Known fidelity differences are tracked as labeled issues.
Projects / Simulator
sts2-sim
Unofficial headless Slay the Spire 2 simulator in C# (.NET 9) against a v0.111.0 baseline. Combat states and RNG streams can be cloned for search. Covers full runs and ascension 0–10.