In the game GraviSoko3D you need to drive 5 green balls into the green cell on the side wall, pushing them with a black ball (first and second levels). The black ball on the first two levels is controlled by an on-screen joystick. At the third level, the same thing, just not pushing, but hitting a black ball as in billiards. To do this, stand with the mouse pointer on the black ball, press the left button and without releasing it move the mouse in the opposite direction from the desired movement of the black ball. At each level, you can turn on the timer for playing at speed. You can also change the location of the on-screen joystick and the orientation of the playing field.