Tetrix couldn't be anything else other than a version of the classic Tetris. As the blocks fall from the top of the screen, you'll have to rotate them and move them to make them drop wherever you want in order to remove complete rows of blocks from the screen in order to not fill it up. There's no need for us to continue explaining as you're so eager to start playing.
The best game of all time has many clones, but the mechanics of tetris games are always the same: Keep filling in the lines and you will win the game.
Sonic Blox is a fun Sonic (and his friends Knuckles and Tails) Tetris style game. Try to complete lines with parts...