Also, whereas Wolfenstein's fortresses all had identical lighting and walls that were always the same height, always aligned in perfect 90º angles, and always with a minimum distance between corners or another wall, Doom featured variable lighting (including flickering and glowing lights, adding to the game's atmosphere), differing vertical heights, and walls that could be angled at any orientation and have any amount of distance to a corner or between walls (including distances too small for you or an enemy to walk through).Īnother feature was expansion of the weapons.