The aim of Code Stack! is to build towers with colored blocks, the lowest block representing the first letter of a word, etc. There are blocks of different colours: green means A, B or C; yellow D, E or F, etc. Five different games use this basic system. For example, each player on his turn builds a tower, and the first other player who finds a corresponding word scores 1 point. Another example: The first player chooses a block, and each player on his turn must add a block on the top of the tower, or accuse the former player of bluffing when he cannot name a corresponding word.