While playing the game, press [Enter] [Left] [Left] [Up] [Down] [Right] [Action]. If you entered the code correctly, Raziel will speak. To disable this effect, press [Enter] [Right] [Right] [Down] [Up] [Left] [Action].
After the intermission sequence when Raziel gets the Soulreaver and he gets controlled by it, Mobius will close the door. Defeat everyone down where you had to turn to the different world, then go in the middle of the lock to go through.
To defeat demons faster, stand in a doorway and fire projectiles at them then feed on their souls. This works best if they hit a wall as you fire.
Keep blocking and sidestepping his attacks while finding open spots for attack until you get about one quarter of his life down. Then, he will run off and enter a room will large heaters and mist around them. When Faustus jumps on to a heater, proceed towards the beginning of the mist trail that leads to the heater and pull the switch to hurt him. Keep repeating this procedure until he jumps up on to a chain, then run to a corner of the room and stay there until Faustus jumps down . He will now try to jump and kick you from far away. If you sidestep his attack, he will hit the wall and will be vulnerable for a few seconds. Keep repeating this until he is dead.