After you beat phsyco mantis get past the cave Merlye will ask you something go threw the door Merlye will get shot.
Go back threw the cave and you can go back threw the door on the east side go to the truck on floor one.Take out box.a.
Once you get to the heliport go threw the vent, in the tank hanger go to b2 there will be four enemeys kill the one that is gaurding a door go in be careful there are lazers crawl threw and you'l get a psg-1 rifle.
Get out you will get a call from cambell.go to Sniper Wolf defeat her.
If you go to a certain door (the only door)you will get in a trap. NOTICE:Get a type of pill in the cave(I can't tell you where.)
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