Getting the Blue Key (12)

Elevator Room: You'll start here. Watch out for an Enforcer right away. Grab the Pistol Ammo on the floor. There's another Enforcer on the elevator, which leads to a locked door – not where we're going. The big door here just takes you back to the Briefing Room.

Hallway: Head back to the Entrance area, then go down the hallway opposite the Briefing Room entrance. As you enter, two Troopers will pop out. Take the left path from here to get to the Mess Hall.

Mess Hall: This room is packed! You'll face two Pig Cops and three Troopers all bunched up – perfect for a Pipebomb. Keep an eye out for two more Troopers hiding behind a counter. You'll find Shotgun Shells near a moving water conveyor belt.

Kitchen: Go through the big door into the Kitchen. On the far side of the water conveyor, you'll find two Small Medikits on the left and an Atomic Health on the right. You can swim down the sink for two more Small Medikits, but that's it. There's a door here leading to a room with two Octabrains. Take them out, then use Pipebombs in this room because there's a Freezer and a Large Medikit inside.

SECRET 3 (Inside Kitchen): Look for a red handprint on the wall in this room. Press it, and a section of the wall next to it will open. Head inside to find a computer and a Forcefield. Hit the computer to disable the Forcefield. Inside, you'll find a Shrink Ray and Body Armor on some boxes. You can also swim back to the main Kitchen area through the sink here.

Bathroom: Now, go back to the room with the two Octabrains (from step 4). You'll see a fan you can break. Crawl through the opening – but be ready! Three Octabrains are waiting for you right away, plus a Trooper chilling on the sink counter. The Blue Key is sitting on that same sink counter, and a Chaingun Cannon is nearby, close to the urinals. Grab the key and you're set!