What do you mean by agent in this context? Does it mean LLMs?
What search problem are you solving for deck building and is MCTS for combat the same as that in Go AIs?
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.