Headphones strongly recommended. Sound carries around corners and through walls where sight cannot — footsteps, gunfire and blades all give away a position you may never see. Hold Shift to walk on your toes: no footsteps at all, at well under half your speed.

The deck is dark. A lit lamp can be seen right across it — douse yours with F to disappear, at the price of being nearly blind. Firing gives you away. A few fixed lamps stay lit no matter what: crossing one means being seen — and that holds even under Stealth, which a wall lamp or anyone's flare will break for as long as you stand in the light.

Every doorway is a powered door. There is nothing to press — walk up and it opens, and it shuts behind you. Shut, it stops bullets and sight like any bulkhead, so a compartment is sealed until somebody is standing in the threshold. It also hisses, and that carries about as far as a footstep: if you hear one cycle, something just moved through the room next door.

Held fire walks your aim off target. The reticle opens as the barrel heats, and where the round goes inside that cone is not yours to choose — so bursts, not magazines. Running makes it worse; walking on your toes is as steady as standing still. Hold right click to brace: the cone all but closes and the weapon tightens with it, at a third of your speed and with the barrel swinging rather than snapping. You can fire throughout.

On touch: left half of the screen moves, right half aims and fires, and the ring at the bottom braces — tapped rather than held, since both thumbs are already busy.