It is a classical tetris game. Rules are very simple. During all game many pieces fall from top of window. Piece falls until landing on another piece or bottom of window. When pieces form horizontal line, this line erases and all pieces above fall down. You earn 10 points for every vanished line and extra 10 points if you vanish more lines. Game ends if there are no place for new pieces. You can move pieces when they fall.

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