Space Hulk: Vengeance of the Blood Angels

Space Hulk: VOTBA Is a GW licensed Doom mod for the Sony PlayStation. You play as a Terminator of the Blood angels in a varity of claustrophobia-inducing missions. The game is played from both a top-down strategical view and in first person shooter mode.

Despite how all of that sounds, this game is FUCKING AWESOME. Your sucky close combat skills makes the genestealers terrifying and the friendly AI is shockingly good for the time. The missions range from easy to HOLYFUCKWHYISTHISHAPPENING with a good difficulty curve. It's doom port so the graphics are basically how you expect... which just serves to make you shit yourself when you hit CQC and it switches to goddamn 3d. Stay away from CQC.

Entirely worth emulating and hopefully worth remaking with better graphics for mobile.