Part 52

After teleporting to a room in section c3a2b with an HEV station and gauss gun ammo, equip the assault rifle and run to the opposite wall with a window. Crouch by the wall to avoid a teleporting vortigaunt, then face the door. Shoot down the second vortigaunt that teleports near the door.

Wait for the first vortigaunt to be killed by electrical discharges. Then, use the HEV station and collect the gauss ammo. Use the exit portal to return to the starting teleporter area.

Proceed through portals 2, 4, and 7 to reach the core area in section c3a2f.

In section c3a2f, stay on the starting ledge and observe the reactor mechanism with rotating platforms and a large circular ring.

Quicksave. Jump from your ledge to the circular ring as it descends to its lowest position.

Land on the ring, turn left, and run along it until you find a ledge with a button labeled "01".

Wait for the ring to rise to the ledge's level, then jump to it (using a moving platform if necessary). Press the "01" button.

Quicksave. Repeat the process: jump to the descending ring, turn left, and run to the next button ledge labeled "02".

Jump to the "02" ledge and press the button. The doors to the central core will open.

Quicksave. Jump back to the ring, then to a moving platform heading towards the central core.

When the platform is next to an open core "door," move onto the door's ledge, crouch-jump through the door, and enter the portal to return to section c3a2c.

In section c3a2c, save your game. Do not enter the nearby exit portal. Instead, go through doors to reach section c3a2d.

In section c3a2d, go to the red wheel on the overhead pipe and use it (jump right before pressing "Use item" if needed). Wait for steam to kill three headcrabs, then turn off the steam using the wheel to access a dark area with an armor battery. (Source notes two armor batteries).

Find the side alcove with a ladder. Climb it, then go down the corridor to a closed door. A scientist will open it.

Go through the open door and collect supplies while the scientist talks.

After the scientist opens the long jump module case, pick up the module. To use it, run forward, crouch, and jump immediately.

When the scientist opens the next door, have him and a security guard follow you through the noisy scanner. Use any available first aid and HEV stations.

Enter the large teleporter chamber, leaving the scientist and guard near the door. Save your game.

Alien controllers will begin teleporting in. Distract them to prevent them from attacking the scientist.

To distract them, you can use the high-up ledge accessible by a red ladder. Run around the chamber to find it. Be aware of limited dodging space and potential damage from falling.

Alternatively, stand on the floor opposite the scientist, near the narrow ledge to the teleporter core. Most controllers should target you. Shoot controllers that appear near the high ledge to get their attention. (Note: Avoid using gauss or gluon guns due to limited ammo for later areas).

When the scientist indicates it's time, quicksave. Run to the spot on the floor opposite the scientist (if not already there).

Continue distracting controllers and dodging their fire until the scientist tells you to go through.

Immediately run along the narrow ledge to the portal and jump into it to be teleported to the "Xen" dimension.