Desktop: ←/A & →/D rotate, ↑/W thrust, Space/K shoot, P pause, M mute, R restart.
Mobile: drag on the left half as a joystick (up = thrust, direction = rotation). Right-side buttons to shoot/pause/mute.
Destroy large asteroids to split them into medium then small. Avoid collisions. Clear all rocks to advance waves. Short invulnerability on respawn.