Around the screen are 4 walls that are gradually reduced to the middle of the screen, on the wall there will be random weak points, in the middle of the screen is your gun that rotates continuously, with a button to shoot in the corner, Mission of the player is to shoot all the weak points on the wall, the wall will stop shrinking and expanding, then appear new weak points and continue to shrink, each time the player destroys all the weak points, the shrinking speed of the wall will be faster, each time you kill the weak point, you will get an increase in score
Victory condition: compare with the modes high score
Loss condition: Wall collides with gun
The game has 2 modes:
Normal: Same as above
Difficult: weak points on the wall will move continuously