The game has a standard Tetris rules but shapes do not fall (there is a decision timer instead) and you can land shapes at the bottom or at the top of the board.
Arrow keys or mouse ? move
Space ? rotate
Ctrl or mouse button pressed ? show the drop place
Ctrl or mouse button released ? drop
Note: Mouse control is a bit difficult at the beginning so you need to activate it in the Options menu if you want to use it.