Per its README, it implements all enemies, all relics, all Ironclad and colorless cards, and everything outside combat across all acts. Other characters’ cards are not listed as complete. It can load combats from save files and is playable in a console.
Projects / Simulator
sts_lightspeed
Standalone C++17 reimplementation of Slay the Spire built for tree search, designed to be RNG-accurate. The README reports 1M random playouts in 5 seconds on 16 threads.