|Up/Down or W/S||Move block up or down|
|Left or A||Move block to left|
|Right or D||Rotate block values|
|Enter or R||Fire a bomb (you get bombs after 3 levels)|
|Backspace||Toggle move method (single-step or fluent)|
|P or Q||Pause|
When the game ends you get your highscore and a verification code (click the screen to copy). This code you can post in any forum or send it to your friends to show them your score.
To check if a highscore is valid copy the code and run Xen.exe - a message box will ask you wheter to check the code or not. If Xen is already running you can press the V key (the game pauses) and enter the verification code directly.