Blokus

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.

There is a solitaire variation where one player tries to get rid of all the pieces in a single sitting.

Components:
Blokus Game Board (400 squares)
84 game pieces (four 21-piece sets of red, green, blue, and yellow)
Each color inlcudes:
1 one-square piece
1 piece with 2 squares
2 pieces with 3 squares
5 pieces with 4 squares
12 pieces with 5 squares
Goal of the Game:

Each player has to fit as many of his/her 21 pieces on the board as possible.

How to Play:
1. Each player chooses a color and places that set of 21 pieces in front of his/her side of the board. The order of play is as follows: blue, yellow, red, and then green.

2. The first player (blue) places any of his/her pieces in a corner square. Play proceeds clockwise around the board (yellow, red, and green), each player putting their first piece down in one of the corner squares.

3. Play continues as each player lays down one piece during a turn.

Each new piece must touch at least one other piece of the same color, but only at the corners.

No flat edges of same color pieces can touch.

There are no restrictions on how pieces of different colors can touch one another.

4. Whenever a player is unable to place one of his/her remaining pieces on the board, that player must pass his/her turn.

End of Game:
The game ends when all players are blocked from laying down any more of their pieces. This also includes any players who may have placed all of their pieces on the board. Scores are tallied, and the player with the highest score is the winner.

Scoring:
Each player counts the number of unit squares in his/her remaining pieces (1 unit square = -1 point).

A player earns +15 points if all his/her pieces have been placed on the board plus 5 additional bonus points if the last piece placed on the board was the smallest piece (one square).

There are unauthorized versions of the game published under various names, including The Strategy Game, Tetris, Blokád (unofficial Hungarian version with cardboard pieces) and The Family Chess Game.