The players take turns in chomping squares out of a bar of chocolate. The player who eats the last square loses.
The game is played on a rectangular grid representing a bar of chocolate - a good size is 5 x 4. The top left square is marked in some way to represent a poison pill:
The players take turns to mark an empty square, and then shade any unshaded squares below and to the right of it to represent taking a bite of the chocolate:
The top left-hand square is poisoned, and the player forced to eat this loses.
In this game the first player, Blue, is forced to eat the last square and so loses:
Other games like Chomp: Obstruction