Play beach volleyball with your friends. The first team to reach 21 points wins (of course, if it also has at least 2 points of advantage over its rival). Each team can touch the ball 3 times, and the ame player can touch it 2 times in the same play.
Z key to serve (keep it pressed, aim with the mouse, release the key). You also use the Z key to shoot to the other side (when you're close to the net and receive a ball from a teammate: keep it pressed, aim with the mouse and release it). Use the X key to pass the ball (keep it pressed, aim with the mouse, block, release). The mouse enables you to move (you always go to the place where the black box is in the screen) and aim when you're close to hit the ball or block (as it was explained). The space bar interrupts the reaction animations.