"Programming in Haskell" by Graham Hutton has a few small text mode games in the second half of the book: Nim, Hangman, the game of life, and Tic-Tac-Toe; and it walks you through the minimax algorithm. The author also implements a solution to the countdown problem, which is hard to explain, so as an example, you're given a sequence of nimbers [1, 3, 7, 10, 25, 50] and the target 765; a correct solution is (1+50)*(25-10).

The first half of the book is more geared towards a newbie to functional programming in general.