Quake II/Cooling Facility

Level objective
The objective for this level is to activate the cooling pump to lower the coolant around the reactor. To do this, you need to fight your way to the pump control room, turn a wheel valve and push a wall button. Having done this, there is more fighting before you are able to return to the reactor.

Strategy
Other than always being on the lookout for Strogg with a suitable weapon in hand, there is no particular strategy needed to get through this level. The path that you need to take is clear, although you will be rewarded for exploring dark corners.

Walkthrough
You enter the level through a large pipe, which opens into a courtyard. You cannot leave the level this way and you will return to The Reactor via a different exit. After clearing away the Strogg, drop down into the courtyard and explore the area beyond the opening opposite. You will find a room with a channel of flowing water which enters from a pipe on the right. At the end of the level, you will be swept down this pipe into a Strogg ambush, so take a look around and plan what you will do. For example, you could decide to hop out of the water and take cover among the boxes on the far side of the channel from where you now stand.

As you return to the courtyard, note the grating that you walk over. At the end of the level, this will be open and you will drop down through it to find the exit back to The Reactor. If you want to go through the level again (to complete the kills, find missing secrets, pick up items, etc.), plan on walking carefully around the edge of the open grating to get back to the courtyard.

Back in the courtyard after this bit of preliminary exploration, there is a button to press that opens a large panel in the floor. Drop into this opening. You will be set upon by some Technicians. Although the way forward is to the left, there are goodies to the right which you can check out now or come back for on your second pass through. To keep control of your position, rather than getting into the water down below and being swept along, walk on the edge of the channel as far as possible. You will quickly come to a turn to the left and see that the channel slopes downwards (see also Secrets, below). Walk on the edge as far as you can. In a room beyond a short tunnel, the channel doglegs to the right and then turns left. In the room are Iron Maidens (three, at hard difficulty). To engage them, you're going to have to hop out of the water but it's a tight space in there with no cover so consider just trying to get past them without taking too much damage (you can come back for them later). Either way, the exploding barrels are not going to be pleasant to have around while you're in the room, so try to get a shot at one to blow them up now. If you're lucky and can entice the Iron Maidens into walking around, you may be able to do them some damage. Eventually, you'll have to leave the safety of the ledge and try to get through this room. Another downward section of the channel will dump you into a large room that is flooded with water. While you are floating in the water you may be able to see back into the Iron Maiden room and do them some more damage.

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Secrets
This level has three (3) secrets, plus a bonus:
 * 1) After entering the flowing water (or walking along the edge of the channel that holds the water) you will first turn to the left and go down a slope.  As this slope begins, get out of the water on the left side and take the ladder down to a lower level.  Here you will find a hidden room with health and ammunition.
 * 2) From the first secret, the flowing water will eventually take you into a large flooded room with two elevators.  Take either of them up to the balcony.  Go around to the right until you are above the water channel and hop up onto the balcony wall on the inside.  Look towards the elevator that comes up directly at the exit door.  On its right, you will see a ledge part way down on which there is a mega-health.  Go forward and jump down onto this ledge.
 * 3) In the room in which you turn the wheel valve to achieve the level objective, there is a hidden room behind the wall diagonally opposite to the door by which you came in.  You may have opened up the wall in the battle against the strogg in the room; otherwise, shoot the wall to break it down.

In addition to the secrets, there are several places in this level where ammunition and health are placed out of sight and may be missed unless you search for them. For example, when you leave the large flooded room (see Secret 2, above) you will enter a small room with a pool of water on one side. Go into the pool, turn around and crouch to find grenades.

(Add content about the "bonus", anyone who knows what this might be.)