| A D | run (or ← →) |
| Space W | jump and climb (or ↑) |
| S | crouch, use switches and doors (or ↓) |
| Mouse | aim |
| Mouse 1 | fire |
| Mouse 2 | special power |
| Right Ctrl / Mouse 3 | previous weapon |
| Insert | next weapon |
| Esc | menu (and lets go of the mouse, which a game captures for aiming) |
As it ran on DOS, or enhanced with coloured lighting, particles and smooth motion.