Part 25

Climb stairs to a ledge to collect ammo. To exit, jump on the railing next to the stairs and run forward to safely drop past an electrified rail.

Approach the large doorway leading to the next area. Retreat to the left corner as vortigaunts teleport in. Wait for fighting to cease, then proceed through the doorway and eliminate any survivors with the assault rifle. Be aware of a vortigaunt hiding in a dark niche on the left.

Use the crowbar to break boards on a doorway to the left. Enter and equip the shotgun. Position yourself next to the security guard until a vortigaunt teleports outside the doorway, then quickly kill it with a double-barrel blast to protect the guard. Bash boxes for .357 ammo and health. Lure the guard into the room across the hallway.

Run towards wooden boxes in the next room to trigger a ceiling collapse, dropping headcrabs. Alternatively, shoot the ceiling with the pistol. Retreat while the guard deals with the headcrabs. Locate a spot near the first aid station behind the wooden boxes, then toss a grenade into the ceiling area to eliminate remaining headcrabs. Access the ceiling area by jump-crouching onto a single box, then a two-box stack, and finally jumping onto the ceiling ledge. Find three armor batteries in the back of the ceiling area, then drop down. Break boxes for another armor battery and use the first aid station if needed.

Whack the guard for his pistol. Quicksave. Approach the end of the area where a marine mans a sandbag-protected gun. To defeat him:

Option 1: Stand behind the large wooden crate on the right until the gun stops firing. Bash the crate with the crowbar, then run forward and jump the track. Move next to the sandbag pile and jump to see and shoot the marine.

Option 2 (safer, requires grenade): Get behind the large wooden crate on the left. Crouch-strafe slowly right until you can see the gun's right edge. Toss a grenade through the gap to the right of the gun to kill the marine. Quicksave before tossing the grenade.

After the gun is disabled, jump to its side of the track. Jump onto the sloped cement beam leading to a horizontal crossbeam. Jump-crouch onto the crossbeam, then jump to a narrow ledge. Use this ledge to jump onto a beam with an armor battery. Slide down the slanty beam and move along the ledge next to the track until you reach the large red "BLAST DANGER" doors.

After the doors open, back up and use the pistol to detonate a tripmine just past the doors, or carefully crouch-walk under them. Past the doorway, crouch-walk slowly towards the ladder. Look down at the walkway below for a marine and sneak-shoot him with the .357 if possible. Climb down the ladder and go through the doors near the marine to find another rail car.

Search the room to the right for a health pack and .357 ammo in a wooden crate. Check the area past this room for a hidden HEV station in a wall niche. Get on the rail car and ride it forward slowly, crouched against the control console. When between the two red laser alarm beams, stop the car and stand up briefly to spot a bullsquid ahead.

Use shoot-and-duck tactics to kill the bullsquid with the .357. Slowly move right on the car to sneak-shoot another bullsquid on the walkway to the left. Once it's dead, crouch-ride the rail car to steps on the right. Get off the car but do not ascend the steps. To avoid activating the turret, jump onto the railing to the left of the steps and crouch-walk past the turret.

Retrieve AR grenades from near the dead bullsquid. Use the rail-walking trick to return past the turret and onto the rail car. Ride it until a ledge with a turret and a door appears on the left. Stop the car, open the door, and shoot the bullsquid past it with the .357, strafing left to avoid its toxic spit. After it's dead, slowly enter its room and use the pistol to sneak-shoot a headcrab around a corner on the right. (Another headcrab may be past the door on the left, but the bullsquid often kills it.) Go to the back right corner of the room and crowbar a barnacle. Look for supplies before returning to the rail car. Ride onward to section c2a2e.

Section c2a2e: ROCKET EMPLACEMENT AND SIDE AREAS WITH BARRIER-RAISING SWITCHES. As you round the corner, crouch and move slowly. Strafe left off the rail car without stopping it. Watch it continue onward.