Move: ← → arrow keys or A / D  ·  Fire: Space (hold for auto-fire)  ·  Pause: P  ·  On phones: drag to steer — your fighter fires on its own.
Watch out for the green Boss Galaga's tractor beam: if it captures your fighter, shoot that Boss down while it's diving to rescue it and fly as a dual fighter with double firepower. Every 3rd stage after stage 1 is a Challenging Stage — hit all 40 for a 10,000-point perfect bonus. Extra fighter at 20,000 and 70,000 points.