O/P or ←→ move   Q/↑ jump & ride grav-lifts   A/↓ kneel   Space fire   Backspace back 5 s   Enter start
Or the buttons beside the screen: ◀ and ▶ run, at the top of each end; the target fires, halfway down its own end; and ▲ and ▼ jump and kneel at the other end, so one thumb runs while the other jumps. Or the screen itself: press near a side wall to run, near the ceiling to jump, near the floor to kneel — both ride the grav-lifts, and the corners do two at once.
Or the mouse, by its own buttons: the left button runs left, the right button runs right, the middle button fires and the wheel jumps and kneels. On the menus, press the line you want, or walk a cursor down them with the wheel or ▲ and ▼ and let the target pick the line it rests on. 1 on the title page opens the options, where the target can change ends.