Simply feeding the Slay the Spire game state directly to an LLM is currently insufficient to achieve stable deck-building or consistent combat performance.

I categorize the game's actions into three types: combat, deck-building, and other interactions.

For combat, MCTS is used. Yes, it's similar to the approach used in Go AI.

For deck-building, a sparse graph search is used: the goal is to rapidly identify winning deck templates within the graph structure.

Only the remaining aspects are delegated to the LLM to make reasoned decisions.