Part 50

Follow the "02 COOLANT SYSTEM" signs until you reach a hall blocked by rubble.

Crouch-walk past the first large piece of rubble on its left, turn right, jump onto the rubble on the floor, move to its other end, turn left, and proceed through the door ahead.

In the next room, equip the gluon gun. Open the door and quickly kill the alien grunt directly across the room.

If crouched when opening the door, the grunt won't see you. Altfire- এর (alternate fire) hornets at the explosive crate on the grunt's side of the room, then fire hornets over the large white hanging object.

If hornets go too high, sneak forward enough to altfire- এর hornets at the barnacle hanging over the upper walkway.

Switch to the hornet gun and sneakily hornet the grunt on the right side of the room. Back up slightly after opening the door to help prevent it from seeing you.

After the initial grunts are dead, use altfire hornets to kill the three barnacles in the room, one of which hangs over the upper walkway.

Find health packs near a dead scientist.

Locate the "COOLANT TANK 02" sign on the wall. The wall is divided into segments by vertical lines.

Quicksave, then place a tripmine in the center of the second wall segment to the right of the coolant tank sign.

Climb the ladder and move cautiously along the walkway until a grunt teleports in and falls through the walkway ahead. If the tripmine is placed correctly, the grunt will be blown up. If not, quickrestore and try again.

Jump over the walkway break and proceed to a door.

Just past the door, use the wheel on the right wall to turn off the steam.

Crouch-walk through the rubble and go up the stairs.

Turn left at the top of the stairs and quickly hornet-shoot the two headcrabs on the walkway ahead.

Use your flashlight to find a third headcrab on the floor near a large orange pump machine, then hornetize it and the three barnacles on the ceiling before dropping to the floor.

Collect armor batteries near a dead scientist if needed.

Use the pump machine's small red lever to activate it.

Use the ladder to return to the walkway and go back the way you came.

Revisit the downstairs room with the scientist and supplies if you need anything.

Go the other way from the hall T-intersection and approach the door you were previously told not to open.

Quicksave, then open the door and run through it.

In the middle of the room beyond, there is a large tank with water at the bottom. If you run and drop into the water quickly enough, the alien grunts in the room will not have time to hornet you.

Find the maintenance access tunnel and swim down it.

When you enter a small room where you can surface for air, section c3a2b will load.

Swim through the short tunnel to the base of the reactor core.

Look up and to the left to see the head of a vortigaunt standing near a ladder on the lowest ledge circling the core.

Look around underwater for two small flow control valve wheels on the walls.

Use either wheel, then wait for the water level to stop rising before using the other wheel.

After the water level stops rising again, float on the surface where the vortigaunt cannot zap you, and wait for it to be zapped by one of the core's electrical discharges.

Climb the nearby ladder to a spot near its top, then look up and locate the stray electrical bolt moving slowly above you.

Right after the electrical bolt passes, climb onto the ledge, turn left, and run for the next ladder.

Quicksave when near the top of the ladder.

When you climb onto the second circular ledge, turn right and run for the nearest ladder. Watch the multiple moving electric bolts to avoid being zapped. If zapped, quickrestore and try again. Quicksave again once unharmed.

On the third and final circular ledge, turn right past the ladder, jump a gap in the walkway, and run for the alcove with the door.

You are safe in the alcove as long as the electrical beam hitting the center of the door does not touch you.

Wait until just after the electrical beam goes off, then go through the door and run to the right.

Go down the corridor until section c3a2c loads.

Go through the "SUPPLY D-301" door and check the shelf for needed items.

Enter the nearby malfunctioning elevator and climb the ladder in the back to ascend.

At the top of the ladder, turn around and jump to the broken elevator door to reach level B.

Go through the "SUPPLY B-301" door and check its shelf for items.

Leave the supply room and go down the corridor until you reach a door on the right leading to a room with a security guard.

Go past this door and turn right, then walk up to the crate ahead.

Immediately back up until you are by the security room door, and have the shotgun ready to double-barrel the vortigaunt that teleports in slightly to the left.