Foundations is a 2 players abstract strategy game that is played using board and pieces of an Isaac set. The aim of the game is getting rid of the value of your pieces by carefully placing them on the board or on already played pieces, thus creating a tridimensional structure developed on different levels. Players take turns placing one of their pieces in ascending order of length. If they can't find space for a piece, they must build on the next level in height so that both ends of the piece rest on top of two pieces of its same colour. When players are forced to build on new levels, they can begin with a smaller piece, but they must then play again in ascending order of length and they cannot play in lower levels anymore. The game ends when players cannot place any more pieces on the board. The winner is the player with less points still in hand. In case of a tie, the winner is the player with less points at the highest level on the board.