Part 5

In section c1a0c, after the surge, return to the test chamber door. Crowbar the revived security guard to death and take his pistol.

Go back to where you picked up the crowbar. Bash out the lower glass panels of the doors to crouch-walk through.

Crouch-walk through the next set of doors and watch the elevator crash. Turn right, climb down the ladder to grab an armor battery, then climb back up and ascend the next ladder.

Quickly exit the ladder and run through the doorway. Use the pistol to head-shot the zombie attacking a security guard to save him.

If the zombie notices you, back away and let the guard shoot it. The guard may also deal with another nearby zombie.

Talk to the guard to make him follow you, then proceed through the open doors to section c1a1a.

In section c1a1a, let your guard shoot the two zombies ahead. You can ignore or crowbar the headcrab on the dead scientist.

At the path split, go straight to the break room and locker room. Vandalize the soda machines. In the locker room, get two armor batteries from the "Freeman" locker and two bullet clips from the "Guthrie" locker.

Return to the path split, turn left, and go up the slanty floor to section c1a1f.

In section c1a1f, follow the hall back to the room from the previous chapter. Shut off the alarm using the security desk button.

Go to the wall hole where the vent covering was destroyed. Lure the headcrab to your guard or let it be crushed by a falling computer bank.

Deal with the second headcrab in the distance by shooting it or luring it to your guard. Crowbar your guard to get his pistol.

Before reentering the computer room, go to the big doors leading to the tram platform. Bash the largest panel on the wall to the right of the doors to open them partly.

Crouch-walk under the upper door, then run to the next set of doors and do the same. Grab a bullet clip near a dead guard.

Kill a scientist by walking onto his walkway and quickly retreating before it collapses.

Return through the half-open doors and crouch-walk through the wall hole back into the computer room.

In the computer room's back left corner, jump onto the slanty computer bank (using a jump-crouch) and crawl through the small crawlspace to drop into a corridor.

Avoid the fallen vent shaft near the windows where a scientist gets headcrabbed.

In the dark room across the hall, kill the chair zombie and smash things.

Near the next area, grab the guard's gun after a security guard and zombie turn intangible. Crouch-walk through the left part of the first set of doors to reach section c1a1b.

In section c1a1b, use the button panel to time your way through the opening and closing doors.

Turn right and move forward. When a houndeye teleports in, back up, then charge and crowbar it as it whines to build a sonic charge.

Do the same to the next houndeye attacking a scientist.

In the next area, deal with two more houndeyes by crowbarring them or using the pistol.

If you jump into the side room one houndeye broke out of, you'll find a first aid station.