Chapter 5: The Wolverine
Chapter 5, Checkpoint #1 (The Beginning of the End)
Mutagen- Shredder 3
From the main area that you start in go into the left door using the pressure plate. You will have to stand on a pressure plate after going to the left and lung at an enemy to progress. Shortly after this there will be a long section of the floor that is a spike trap. In the middle of this section to your left will be a boarded up doorway. Break the boards and enter the room to get the mutagen.
Mutagen- Unstoppable 3
When you go to the left part of the main area that you started in there will be a statue that you must push down, so you can go through the main door. When you get to the very top, you will have to fight a flaming machete champion and all of that. Kill them all and look at the wall directly behind the movable statue. It is breakable. Break it and you will have your last mutagen. Achievement!! Not really...but at least you have them all now. :P