I still wonder how well a computer could handle games like magic: the gathering which don't simply include hidden information and randomness, but include cards that change the rules of the games themselves and where the interactions of cards can produce crazy effects that are hard to predict before they occur.

Add in the fact that each player needs to build their own deck (choosing from 20,000+ cards) and that new cards are printed regularly, significantly shifting the expected metagame, and building an AI that can routinely win in a larger card pool format like Modern or Vintage seems absurdly difficult.