Blokus (officially pronounced "Block us") is an abstract strategy game with transparent, Tetris-shaped, colored pieces that players are trying to play onto the board. The only caveat to placing a piece is that it may not lie adjacent to your other pieces, but instead must be placed touching at least one corner of your pieces already on the board.
Blokus Game Board (400 squares)
84 game pieces (four 21-piece sets of red, green, blue, and yellow)
2-4 Players Ages: 7+