Single Player: Use the arrow keys to move and spacebar to shoot
Multiplayer: First player are the same controls. Second player uses WASD keys and V to shoot.
You have 3 lives. Getting hit by an asteroid or an enemy missile will cost you 1 life.
Every shot to the enemy spaceship increases your score by 1 and takes
some health from the enemy spaceship. As your score gets higher, more asteroids start to fall.