This is BIG BOSS... GREY FOX remained the following flowchart before his trace was lost. It indicates the route of infiltrating OUTER HEAVEN. Act by following this chart when you transgress the fortress.
Note that this chart is incomplete. SOLID SNAKE, act by your own discretion in the phase that follows after this chart. Wish your good luck...
...OVER.

 

Infiltrate Bldg 1

(Bldg 1, 1F from here)

Infiltrate courtyard and trucks

Obtain ration

Obtain card 1

Obtain binoculars

Infiltrate inside the room in south (use card 1)

Obtain gas mask

Go north and look for western elevator

Infiltrate inside the truck (left one) next to the elevator

Obtain handgun

Get into the elevator and go up to 3F

(Bldg 1, 3F from here)

Evade the surveillance camera and go south

Look for the eastern elevator (that takes you freely to basement, 1F, 2F, 3F and rooftop)

Look for GREY FOX

 

	Outer Heaven Conceptual Drawing
Bldg 1	Bldg 2	Bldg 3