Space Blaster is an auto-fire gallery. Your ship sits on the bottom rail and shoots on its own. You only steer left and right to stay under incoming craft. A tank needs two hits. Three collisions end the run. Density and speed rise with your score. There is no separate Fire button — missing a craft is a positioning problem, not a trigger problem.
Hold Left or Right, or use the arrow keys and A/D. Release to stop. There is no separate Fire button.
Destroy as many craft as you can with three hull hits.
Steer a climbing rocket with inertia.