Quadrata

Quadrata logic game has simple rules, but playing well requires sophisticated strategy.
The goal is to place pieces on a grid so that they form a square. The player who makes a square first wins.

Quadrata is played on an 11-by-11 square grid board with the four corners missing. Players take turns placing pieces on the board. Each player begins the game with 20 attacking (colored) pieces and 6 blocking (white) pieces. The object of the game is to outmaneuver your opponent and be the first to outline a square, called a quadrata, by
capturing its four corners with your colored attacking pieces. You use the blocking pieces only for blocking your opponent's squares; they don't count toward making squares of your own.

On each turn you place one attacking piece on the board. Optionally, you can place any number of blocking pieces, up to the six allotted, before placing the attacking piece. If both players run out of attacking pieces before either has made a Quadrata, the player with the most unplayed blocking pieces is declared the winner. If each has the same amount of blocking pieces (or if neither has any), the game is declared a draw. A winning square can be any size and orientation, and this is why playing Quadrata well requires strategy.