Unlock the computers (and the first door)
To Unlock the Computers at the beginning of the game, you must get to the part where you posses the soldier. Then go back to the lab and talk to the guy standing in the white lab coat. He'll say that everyone is spooked about the ghost that got loose (you) and will unlock the computers. Just read the computer screens to find out the code for the door.
Slug Boss Hint
After recuing Bryson and entering the lift, you will see a short cutscene in which Bryson hints at Project Z, and then gets eaten by an ugly-looking slug beast. You begin an enclosed circular space. There's a door at the end, but don't try it; it's locked. The boss sits in the center and attacks in four ways. He hides his head behind his claws and spits single or multiple projectiles, (attacks 1 & 2) or a laser beam. The single projectiles are easily avoided, but the multiples get progressivly harder to escape. I recommend dispossesing the host. The projectiles won't harm you in ghost mode. The laser is also relatively easy; just run away. The final attack is a bit harder; he wil curl inside his shell, and roll around the area, trying to run you over. He will be either on the inside "lane" or the outside, never both. Watch how he approaches and quickly move to the opposite lane to avoid being hit. There is health along the wall if you need it. After using attacks 1-3, the monster will peak out from behind it's claws and roar at you. Use this oppurtunity to shoot it in the face; it's claws protect it when it's attacking. After you cause enough damage, he will retreat inside his shell, and start to glow. That is the signal. A small opening at the front opens and closes, but disappears quickly, so toss a grenade inside with the Z button. After a few such explosions, he will retreat agin to his shell, but he won't glow. Instead, he will roll around the arena very fast, stopping randomly and opening the hole. You must follow it and throw another grenade inside. After about four total grenadings, his shell will fall apart, and the beast will crawl back down the elevator shaft, leaving shell parts and a very angry Bryson behind. But don't worry; you'll see that monster again soon...
For the first one with John Raimi in the beginning of the game when you verse the Creature, just dodge and shoot at its mouth when it roars.
For the first Cord fight, stay by the door you entered through and dodge the bolts. When you hear a beep start shooting him, when he falls disposses your body and enter the grenade. Roll behind Cord and explode. Repeat until he leaves. If you miss him once run away because the grenades take out about half of your life.
For the second Cord fight after the puzzles, hide your engineer away from the gun cams into a corner. Use the gun cams first and then the soldier behind him every time.If you don't kill him with the soldiers but he only has a little life left use the engineer.
Here's some help on the 2nd fight with the Slug boss... You'll see the giant slug covered in a mess of lab equipment, notice the gas tanks! When he starts rolling around get in the corner where you can get way back in there, when it comes around fire as much explosives, ammo, ANYTHING at it you can! You'll notice things blow-up on it. You should see blue flames coming out of him. That's great, you can just stay in that corner the whole time and defeat him. It's as easy as that.
Beating Cord 2nd Time
When you enter the room, dispossess the main host. On your right is a tank with a knob thing. Possess the knob and press A. All but one of the soldiers will be scared. Possess any of the soldiers and shoot the one that isn't scared until he's dead. Now that Cord focus ONLY on Cord. DO NOT SHOOT THE OTHER SOLDIERS!!!! Once the soldier has died, possess another one and repeat until all are dead. If he isn't dead yet, possess a gun cam. If both gun cams are down and he still isn't dead, use the main host. This is a much easier way to kill him.
How to beat Alexander Volk
Alexander Volk is the old man in a wheel chair you a lot of times in the game but now that you got your body back you have to stop his evil plans so this is how we do it: First of all his wheel chair can fly and your weapons are kinda useless, as a priority kill all the ghost that try to posses you using grenades and if you get possed press "A" as fast as you can to get free. When you kill all the ghost attack Volks until he launches misiles at you, at that moment disposes yourself and posses the misiles and control them and make them go to Volk to make him some reasonable damage, more ghost will apear after that only repeat the proses until you kill him. I wish you good luck and dont forget to use your hyper speed to get health paks and evade attacks fast.
1 Shot Kill With Secrect Character
Go to multiplayer and pick the storage level. Find the bunny closest to the stairs. Posses the bunny and then go up the stairs into the vent thats blue. Go in the vent and go up until you get to a ledge then get to the top. When you get to the top of the level you go on the rafters (pipes in the air). When your up there unposses the bunny and go through the wall where the light is. If you don't want to do that just simply use the bunny jump on the roof and go in the vent that is there. When you go through the vent or wall you will see a secret character that has a pistol and that will kill the opponents in one shot. Now open the door and let the opponents come to you and when they do SHOOT EM'...