The chapter will start off after crashing the Blackbird.
You will have to check on Wolverine after getting off the Blackbird.
You can also get yourself an achievement for "bitch slapping" Wolverine enough times.
Head through the tunnel near the crash site, once you're done slapping Wolverine.
Fight the enemies in the area next to the tunnel you've just gone through.
A new enemy will appear; a huge Sinister clone. He will try to pound the ground and cause a stream of energy to head your direction, best way to avoid his attacks is to use the teleportation. The fastest and the most efective way to take him out is using the shotgun.
Head to the walls with green lights on after taking out the big Sinister clone. Use the green lights to wall jump.
After reaching the next area, you will encounter a lot of enemies attacking you. Try to take cover as much as possible.
Once you've dealt with all the enemies in that area, Cable will appear and start explaining what's going on.
Deadpool obviously can't stand Cable's boring explanation, so you will have to press 'Z' to make Deadpool shoot himself in the head.
A few moment later, Deadpool will wake up with a note and a knife stuck in his chest. After pulling the knife out of his chest and reading the note, you will have to meet Cable at the north end of the city and find your 'totally real' fan girl.
Take out all the enemies inside the building and head outside.
Deal with the enemies next to the platforms.
Once you've dealt with all the enemies, use the platforms to climb up on the surface.
After reaching the surface, you will encounter a new type of enemies that will try to attack you with his projectiles made of purple energy.
You can choose to fight him, or head directly to the power cell and grab it.
After grabbing the power cell, head to the Sentinel arm and insert it inside and use the cords to control the arm and clear the way so you can go through the building.
Head through the ruins of the building.
After moving through the destroyed building, you will meet your "real" fangirl.
The fangirl turns out to be Cable.
Watch the rest of the cutscene.
Once the cutscene is over, you will have to take out the enemies guarding the tower. Doing so will take a while, since the combat sequence is really lengthy. However, Cable will help you out with his really powerful gun.
After taking out the enemies, head inside the tower and interact with the machine found in there.
The machine will activate the magnetic tower, which will make the metal platforms float around the tower; helping you get on top of it.
Once you're on the top of the tower, use the buttons shown in the game to deal damage to Sinister.
After killing Sinister, it turns out that he was a clone.
Cable will ask you to get him two parts in order to finish building the Sentinel boot.
Go through the building Cable's pointing at.
You will find another power cell after leaving the building, climb up the structures and grab it.
Place the power cell inside the Sentinel arm and lower the arm so you can reach the balcony and enter the building where the first part is located.
Fight the enemies inside and grab the second power cell located on the higher level.
Use the power cell on the Sentinel arm located outside the building.
Place both Sentinel arms like this so you can get to the first part needed by Cable.
After grabbing the first part, get back to Cable.
After returning to Cable and giving him the first part, he will tell you where the last part is located.
Move through the area and kill all the enemies and grab the power cell.
Place the power cell inside the Sentinel arm and fire the Sentinel arm three times to destroy the building.
Go through the building you just shot at with the Sentinel arm.
Grab the second power cell and head back to the Sentinel arm and insert it inside.
Move the Sentinel arm around and destroy the wall preventing you from reaching the building where the last part is located.
Head inside the building and grab the last part.
Return to Cable.
After giving the last part to Cable, Deadpool will jump inside the Sentinel boot and take off.
You will start landing in various places, use the gun mounted on the Sentinel boot to shoot the enemies.
Deadpool will lose control of the Sentinel boot, it will continue to hop from location to location. This will be the end of the chapter.