Level 1:
Deplace yourself with the four [REPLAY] keys.

Level 2:
Shoot with the [7], [8], [9], [4], [5], [6] and [1] keys.

Level 3:
Deplace yourself with the four [REPLAY] keys, shoot with the [F1] key.

Level 4:
Deplace yourself with the four [REPLAY] keys, shoot with the [F1] key.