The base AI that came with the card gaming engine that we developed agents for during university was called "thumb"...it always played the cards closest to an i

The base AI that came with the card gaming engine that we developed agents for during university was called "thumb"...it always played the cards closest to an imaginary thumb of the hand holding the cards. Some people played 10+ games against it thinking it was really impressive :D More sophisticated rules based card game agents can actually look very good unless you play a huge number of hands against them (depends on the game structure though, trick taking games work well, poker agents can usually be understood quickly even though an agent that simply plays very aggressively usually looks strong for a bit).