Space hulk is scary as shit.
Quiet corridors. Distant growls and other mysterious noises. Mission briefings that say ominous shit like 'the are numberless' and 'hesitate and you will be lost'.
Then when the game starts, even though you are in control of five superhuman warriors with the best weapons technology known, you soon realise that they are in no way prepared for the kind of shit they're walking into. You have to stay cool and think quick, but that's tough with the kind of tension the game creates. Even if you think you have good tactics, that goes out the window pretty quick when one of the video feeds turn to static and you hear the distant, blood curdling scream of a marine being torn apart.