At the main menu, press L1, R1, L2, R2, Square, Circle, Triangle. Start a new game to begin with the Soul Reaver and Iron Armor.
Defeating Faustus
The easiest way to defeat Faustus is to block until your Fury bar glows and hit him with that. Dodge every time you see him try to use a glyph attack. It only takes two Fury hits to get him to go to the furnace room. Load up the Mist glyph and head to a steam spot immediately. You should be able to turn on the furnaces without taking too much damage running from steam spot to steam spot. Once he gets burned and starts running around the rafters, just run around the edges of the room until you hear him drop down. Try to be near a corner or wall. Wait for him to jump at you, then jump or dodge his attack. Once he hits the wall, he will be stunned. You can hit him with a good combo before he jumps back up to the rafters. Repeat this two or three times and he will die quickly.
Defeating Magnus
Magnus is fairly simple to defeat. When he is standing in the middle of the giant fountain that is surrounded by statues, run and hide behind the closest one. He will try to burn you, but will hit the statue. Jump out and shoot him with Telekinesis very quickly. Once he falls into the water, run behind the next statue until he tries to burn you again and repeat the process until he leaves. It should only take three times. In the next room you will see giant statues holding scythes. Magnus cannot burn you anymore, but he will charge into you. Do not bother hitting him. It does not do any good. Get in front of one of these statues and get him to charge you. When he does, dodge him and he will run into the scythe, breaking it. Once it breaks, you will see a glowing telekinetic switch. Jump onto one of the boulders or platforms so Magnus cannot get you, and shoot the switch. The statue will open its arms. Do that to all of the statues and the gigantic statue in the middle of the room will be put back together. Get Magnus to charge into the base of the weapon that the statue is holding the same way as before. When it breaks, make him charge into the base until the statue falls and crushes him. Just stand next to it and shoot Magnus with Telekinesis. That should make him charge you.
Defeating Marcus
You will fight Marcus in a cathedral, on the bottom floor first. On the left and right sides of the room are switches, one on each side. These switches activate bells which disrupt Marcus' concentration and leave him vulnerable for a short time. Hit one switch, then run to the other switch, hitting Marcus on the way. Continue this until his "puppets" disable the bells. Go up to the second floor. Marcus will just run around until you kill him. Use the jump ability to alternate between sides, hitting him on the way. Once he dies, you obtain the Charm ability.
Just hit the bell switches and hit him when he is stunned. When his puppets disable the bell, you can still ring it by jumping into it. He is easier to locate that way. Then, just run around killing enemies while hacking up Marcus, occasionally ringing the bell. You can avoid the puppets altogether, but you will want to build up your Lore bar as much as possible.
Defeating Sebastian
When the battle starts, run the opposite way of the mist shooting out of the grates. Jump over when needed. Sebastian will not jump, thus burning himself. In his second phase, you must be directly behind one of the mists and follow it around until it stops. When he grabs onto the wall, put the purple portal object between you and him. He will run directly into it. Do this three times to continue. In his third phase, he will try to destroy the stone. Jump up there so he gets off and charm the peasant in the room to unload all of the mist on the ground. His fourth phase is just a fist fight until the finish.
On the ledge in the swamp just in front of the first forge (the dark forge) are some crows. Do not go near them. If you do, you can still get inside but you can never open the door again to get out. Getting out requires an intermission sequence with Voridor. Since the crows are his messengers, if they disappear the intermission sequence will not happen thus, you cannot get out.
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