In Tetris, as blocks fall down from the top of the screen, you try to align and rotate them to form rows. Whenever you form a row, it disappears and the blocks above it are lowered by one tile.
In this version of Tetris, here's how the scoring works: Whenever you get one or more rows, the number of points that you get equals 1000 times the number of rows squared. With "Ultimate Challenge Mode", the colors of all of the blocks in rows have to match. Pretty difficult, don't you think?
Here are the controls: To move a block left or right, use the left or right arrow keys. To rotate a block, use X. To move a block down faster, use the down arrow key. UPDATE: You can now move blocks 10 times as fast by holding down the CTRL key when moving blocks with the arrow keys. This is especially useful in Hardcore mode. In Hardcore mode, the grid is 125 x 125. Also, the rotate/select key has changed -- it is now X. This game was last updated on 1/20/2009.