1. Mouse click green flag to start the game. 2. Press 'Space' bar to shoot the rock. 3. Move the rocket up and down by arrow key. 4. Move the rocket front and back by arrow key. 5. Each destroyed rock will give one score. 6. Accumulate score for level up and weapon upgrade. 7. Win the game by score 300. 8. pick up repair pack (speaker) to restore life bar.
- add more rock. - add healthbar/lifebar. - add repair pack.
