Half-Life 2 (PC) guide
by KeeperBvK aka Burkhart von Klitzing
Contact: KeeperBvK@web.de

Dedication: I dedicate this work to my beloved dad who passed away on the 
            07/13/2005.
            I always loved you and I always will. Thank you so much for the 
            time we had.

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                             0.2 Version History
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Started working on this on May 30.

1.0: Finished on 06/18/2006, 179 KB large

1.01: Finished on 06/22/2006, 179 KB large
- Added www.supercheats.com

1.02: Finished on 07/09/2996, 179 KB large
- Improved on the museum section of the walkthrough.
- Added the secondary fire of the Pulse-Rifle as an alternative way to
destroying the Striders, thanks to Bruce Zhang.

1.03: Finished on 07/26/2006, 180 KB large
- Changed Dog to D0g. Thx to Robbie Vancourt.

1.04: Finished on 10/27/2006, 180 KB large
- Walker Wilson told me that the pheropods can also be used to distract
Combines, so I added that.

1.05: Finished on 01/18/2007, 180 KB large
- Added the secondary fire for grenades, thx to Dominic_rules.

1.06: Finished on 02/17/2007, 180 KB large
- Added www.dlh.net and www.mogelgott.de

1.07: Finished on 03/12/2007, 181 KB large
- Added www.honestgamers.com.

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                                0.3 Contents
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                                               | Latest Update | Search Key |
-----------------------------------------------|---------------|------------|
0.1 Legal Stuff                                |      1.07     |            |
0.2 Version History                            |      1.07     |            |
0.3 Contents                                   |      1.07     |            |
-----------------------------------------------|---------------|------------|
1. What is Half-Life 2?                        |      1.0      |     AAA    |
2. General Hints                               |      1.0      |     BBB    |
-----------------------------------------------|---------------|------------|
3. Walkthrough                                 |      1.0      |     CCC    |
  3.1 Chapter 1 - Point Insertion              |      1.0      |     CC1    |
  3.2 Chapter 2 - A Red Letter Day             |      1.0      |     CC2    |
  3.3 Chapter 3 - Route Kanal                  |      1.0      |     CC3    |
  3.4 Chapter 4 - Water Hazard                 |      1.0      |     CC4    |
  3.5 Chapter 5 - Black Mesa East              |      1.03     |     CC5    |
  3.6 Chapter 6 - "We don't go to Ravenholm..."|      1.0      |     CC6    |
  3.7 Chapter 7 - Highway 17                   |      1.03     |     CC7    |
  3.8 Chapter 8 - Sandtraps                    |      1.0      |     CC8    |
  3.9 Chapter 9 - Nova Prospekt                |      1.0      |     CC9    |
  3.10 Chapter 9a - Entanglement               |      1.03     |     C9A    |
  3.11 Chapter 10 - Anticitizen One            |      1.03     |     C10    |
  3.12 Chapter 11 - "Follow Freeman!"          |      1.03     |     C11    |
  3.13 Chapter 12 - Our Benefactors            |      1.0      |     C12    |
  3.14 Chapter 13 - Dark Energy                |      1.0      |     C13    |
-----------------------------------------------|---------------|------------|
4. Weapons                                     |      1.05     |     DDD    |
5. Enemies                                     |      1.02     |     EEE    |
  5.1 Combine                                  |      1.0      |     EE1    |
  5.2 Xen Aliens                               |      1.0      |     EE2    |
  5.3 Bugs                                     |      1.0      |     EE3    |
  5.4 Heavy Gear                               |      1.02     |     EE4    |
  5.5 Small Machines                           |      1.0      |     EE5    |
-----------------------------------------------|---------------|------------|
6. Closing Comments                            |      1.0      |     FFF    |
7. Experimental                                |      1.0      |     GGG    |
8. Credits                                     |      1.05     |     HHH    |
-----------------------------------------------|---------------|------------|

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                          1. What is Half-Life 2?                         AAA
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Half-Life 2 is the sequel to Half-Life. Now who would have thought? Half-Life
probably was one of the biggest gaming surprises in 1998 and together with
Starcraft it showed what the PC was capable of in terms of gameplay. Other
than Starcraft which was also released in 1998, Half-Life took graphics a
step ahead, too. Half-Life 2 (being an Ego-Shooter like HL1) also boasted
great visuals, has an extremely well crafted sound and tries its best to be
an intelligent representative of its genre with lots of dialogues, trigger
events and a fantastic physics engine, theoretically allowing for massive
possibilities of jerking around or advancing in the game.
You are Gordon Freeman (again) waking up in City 17 after having accepted to
work for the mysterious G-Man. Will our beloved, charismatic, nerdy hero shed
light onto some of the mysteries that are still unsolved? I know the answer,
but I won't tell you...yet.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                               2. General Hints                           BBB
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Try not to use the flash light while diving as it also uses the same energy
as your air supply.

Holding down the jump key makes you stay on the surface when swimming.

Yellow lambda symbols painted onto the wall usually indicate there's
something good around, so search for items nearby when seeing one of those.

Small crates with a yellow sticker saying supply contain just what it says:
Supplies, so open them. Also note that these boxes don't always contain the
same items. They seem somewhat intelligent, as they hold whatever you are
most in need of when opening them.

Metal crates with an ammo sign on them contain an infinite amount of this
ammo type, so open them as often as you want to and maybe use the
corresponding ammo for a while, backtracking to the crate to regain your ammo.

The buggy has an SMG ammo crate at its back.

Use explosive barrels to your advantage: Shooting them twice sets them on
fire so they explode after a few seconds; shooting them thrice blows them up
instantly. Oh and please don't ever use your crowbar on them. You can't set
them on fire with it.

When aiming over great distances, zoom in via Z, take aim and zoom out again.
This allows for shorter cross hair moves.

Don't rely on your squad mates. You might sometimes hide and let them do some
of the shooting, but don't use the squad commands or greatly change your
style of playing when the allies are around. They don't take a lot of damage
and they are far less effective than you should be.

There is no friendly fire on the rebels' side, except for explosions. Hence
you can accidentally hit your allies as often as you wish and run around in
front of your buddies even when they are amidst a fire fight. Just don't drop
a grenade, or miss-throw an explosive barrel or such.

It is possible to duck and still fire when manning a stationary machine gun.
While this gives you some protection it also probably lowers your precision,
so only do it if you desperately need to save every single health point.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                                3. Walkthrough                            CCC
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This guide was written for the hard difficulty setting. As far as I know the
number and position of enemies are the same for every difficulty, so this
guide also works perfectly for easy and normal.
I divided the walkthrough into the chapters given by the game and I further
divided those into the various areas that are connected by loading pauses. To
allow for an easier navigation of the guide, I also named those areas, trying
to omit spoilers given by the titles.


-=-=-=-=-=-=-=-=-=-=-=-3.1 Chapter 1 - Point Insertion-=-=-=-=-=-=-=-=-=-=CC1

[City 17 Train Station]

Be awed by the stunning face textures and animations of the G-Man while you
can: You won't be able to come up this close to him in a while. He says
something about a mission (remember accepting to work for him at the end of
Half-Life 1?) and then you wake up in a train heading for the City 17 station.
Valve definitely seems to like the idea of beginning a game in any sort of
transport devices. Disembark the train only to be flashed by some sort of
sentry drone. It is just scanning you, so don't worry. As you go on, though,
you see some masked humanoid creatures, called Combine, working as the local
poilce which can already hurt you although you are still amidst the prologue.
Simply don't touch them or throw objects at them and you're in no danger.
Listen to the old man (Dr. Breen) on the big screen to further realize you
are in some sort of totalitarian city, reminiscent of Orwell's 1984. Take a
look on the right to see an alien from HL1 cleaning the floor. Finally
everybody should have realized there is something strange going on in this
world.

As you move on you can listen to some civilians further deepening the feeling
of something bad going on, but luckily Valve gave you the Source Engine,
meaning you can throw bottles at people, rip out a phone receiver, get
infinite cans out of a vending machine (like in HL1) and so on to distract
yourself. After a while you are told to enter a cage and to follow a Combine
past an interrogation room (look inside to see some civilian explaining
himself and a Combine closing the viewing hatch) into another interrogation
room. Oh oh, he wants to take care of you on his own, even turning off the
cameras...phew, it's Barney; your old pal from Half-Life 1. After a short
conversation with Dr. Kleiner via the terminal the Combine get suspicious and
try to enter the room. Hurry, leave the room through the door Barney opens
for you...or stay a bit longer, hop onto Barney's head and relax. The Combine
won't come in at any time.

As you enter the dirty storage room you are given your first assignment:
Press E to pick up objects (crates in this case) and use this "talent" to
build a stack under the window so you can leave the room into a small court.

[Leaving the Station]

Enter a new part of the station and watch one of those wicked guards tossing
a can onto the ground, telling you to throw it into the trash can. Do so and
he will let you pass. Exit the station via the door on the left, allowing you
to get a view of City 17 and especially of the citadel in its centre. Take a
right, watch another interrogation in a small room and move on to a street
barricade. Climb up the ladder in the alley on the right and drop down onto
the crate on the other side of the fence. On the left you can see your first
strider; War of the Worlds, anyone? Follow the path past two civilians,
talking about the Combine investigating lots of buildings, to a play ground.
And, oh goodie, it really is a play ground: Pick up the doll making a fun
sound, hop onto the swings, drop a concrete block on the teeter totter and so
on. Can't just everybody play like that? The rotten HL2 world would be a
better place for everybody. Anyway, enter the building on your left once
you've had enough.

[Miscount]
There's only one possible way: Into the hallway with a few Combines standing
up ahead. Get into the kitchen, talk to some people and again enjoy the
Source Engine as you pull the TV out of the wall and throw it through the
window (eventually hitting a Combine down below). Proceed to the end of the
corridor and listen to the announcement: They have detected there's a person
in your sector that doesn't belong there...you! Run up a storey (any other
paths are blocked either by locks or by Combines) and into a room a guy waves
you into. Don't waste too much time now, as the enemies beat their way
through your newly found allies, but you're not in a big hurry. At the other
end of the hallway you'll have to walk up another set of stairs to yet
another room guarded by a civilian. He tells you to move on quickly, but
actually you can stay in that room and go to the bathroom or such, given he
manages to hold back the Combines as long as you wish to stay.

[Cutie]
Up to the loft and quickly out of the broken window onto the roofs. By now
the Combines should have come close by, starting fire from behind. Stick to
the right wall and carefully walk along the ledge not falling down into the
abyss. Eventually you reach a window to climb in, bringing you into another
loft. Go down the ramp, take a right and don't panic as a Combine busts open
the door. Simply turn around, go to the other door and...see that one also
get smashed open. There's only the way back up the ramp left, so take it; or
at least try to. It breaks as you hop onto it so be a man about it and stay
where you are so the Combine can beat the crap out of you. After going down,
Alyx arrives to the rescue. Follow her into the lift. Listen to the one-sided
conversation and finish the first chapter.

-=-=-=-=-=-=-=-=-=-=-=-3.2 Chapter 2 - A Red Letter Day-=-=-=-=-=-=-=-=-=-CC2

[Face Humper]
Follow Alyx to the first yellow lambda symbol in the game. Every time you see
one of these you know there's something good around. In this case Ms. Vance
opens a secret path to Dr. Kleiner's lab. Listen to the dialogue between the
two characters and also Barney joining it after a while, and distract
yourself a bit by teleporting a cactus, looking through the cool lens,
touching the little hula-girl-figurine, discovering an old photo of Dr. Klein
on the pin wall, having a look at an old picture from Black Mesa or maybe
just hopping onto any character's head and staying there for a while. ^^
Eventually Barney walks into a small storage room, finding Lamarr who turns
out to be a debeaked and sexually active Face Hugger. Put on your Hazard Suit
and tank some suit energy at the Combine power station in the corner of the
main lab room.

Then enter the teleporter room and get your first look at Alyx' father (Eli
Vance) on the screen. As Alyx is about to be teleported something seems to go
awfully wrong...great machinery: It's only the plug that has fallen off. Put
it back into the wall and activate the switch to both finally transmit Alyx
and to get some exaggerating praise from Dr. Kleiner. At least Barney shares
your thoughts and cracks a nice joke about it. ^^ Now it's time to be
teleported yourself. Step into the transmitter and watch yourself being
transported to various places thanks to Lamarr. Oh goodie, Dr. Breen now
knows you are in City 17. Oh well, at least you don't get eaten by that ugly
fish and after finally ending your travel outside the lab near some Combine
scanners you are in a better condition than President Scroob was in
Spaceballs after being teleported.

Anyway, you are told to hurry, yet again there's no need to. Drop down and
search for a door behind another fence, leading you to a passage that's
blocked by some wooden bars. Hmm, how to get through? Barney joins you above
giving you the original, famous crowbar from Half-Life 1. Slash your way
through the wooden planks and a crate to reach the first (unarmed) enemy to
beat: A Combine Sentry Drone. Drop down and quickly take a left into the
train, as some Combines open fire from up above on the right. Hack your way
through the wagon, leave it and hide behind the train on your left since
another train is coming in, which might roll over you. Get rid of another
sentry drone and follow the incoming train. Zip in between two trains on your
left without stopping and enter another wagon nearby. Climb up the ladder,
turn left and jump onto the wagon ahead and over the fence while being
attacked from behind. Swiftly move on, crack the lowest wooden bar at the
opening and go down the ramp.

-=-=-=-=-=-=-=-=-=-=-=-=-3.3 Chapter 3 - Route Kanal-=-=-=-=-=-=-=-=-=-=-=CC3

[Battle on Rails]
Refresh at the health station on the left wall. Hear that cry for help? We
can't ignore that, now can we? Haste around the corner and smack the pistol
wielding Combine with your crowbar. You should be able to catch him off guard,
allowing for a few blows before he and his companion start attacking you.
Once the first one is down, go for the Combine with the tazer stick. Go back
to the health panel if you haven't depleted it before this struggle. Then
move on, go up the ramp to the locked door and stay there, waiting for
another Combine to walk down the stairs. Aim for his head. Move on until you
see daylight coming down. Around the corner is another Combine whom you
should give a head shot.

Step out of the dark, walk down the metal stairs outside to trigger a train
coming to a halt right where you need it. Go back up and use the train to
reach the other side of the trench. Turn around and blow up one of the
explosive barrels to buy yourself some more time when breaking the upper
wooden plank in the entrance to the house. Enter it and break apart another
Sentry Drone while watching out not to come too close to the windows, as
infinite Combines aim at you from the other side of the trench. See the
yellow lambda symbol on the left wall? And do you remember what I said about
it? Approach it to find some ammo and health. Move over to the other room and
simply hop onto the explosive barrels and crawl out of the house instead of
wasting a bullet on the barrels.

Stay left of the exit and aim for a barrel on a ledge up ahead. Its explosion
takes care of some Combines nearby. Next, look at the small crate with the
yellow sticker on it. Yellow? Seems like some Ivan Pavlov-experiment to me,
as yellow once again means goodies, so keep in mind to watch for those small
crates throughout the game. Move on and climb over the deformed fence which
gets you back into the line of sight with the endlessly respawning Combines
on the other side of the trench. Speed to the containers on the right and
crawl through the vent (picking up some more items) still not getting you
away from those guys.

Continue to the right and drop down onto the pallet to avoid falling damage.
Shoot the barrels and watch out for some more barrels rolling down the stairs
around the corner. Hitting them, too, should take care of any Combines around,
giving you the time to pick up some suit energy under the stairs. Watch out
for the incoming train, go up and kill two more Combines before it's time for
some serious fun: Pick up one of those explosive barrels (I hope you left at
least one) and move on. Two enemies will hop down to the rails behind the
force field. As they do, they are unable to attack, allowing you to somewhat
safely toss the barrel near them and shoot it.

Do you still have one of those red barrels intact? Great if you do, since you
can pick it up and drop it near the other force field now. Then go up the
stairs and step onto the metal bridge to trigger lots of Combine Soldiers
closing in from where you placed the explosive gift. Shoot it from here when
they are close to it (if you aren't that confident in your aiming skill,
place the barrel at the force field you are about to get past and shoot it
after going down). Break the crates ahead and go down to see some additional
Combines. If you want to you might get back up and to the medical energy
station to clear the whole area once and for all. The loads of ammo and the
medical panel should outweigh any risks here. Otherwise you can drop down
behind the force field and kill your enemies from here, but in this case much
of the ammo that's being dropped probably stays out of your reach as you
cannot get back to the other side of the force field. Now relax and restore
yourself at the new medical station and the small crates.

An alternative way of dealing with these hordes of Combine is to speed over
the metal bridge, run down and keep running to the left, avoiding any direct
battle with the humanoids, but if you choose this alternative you have a
rather hard time nabbing the suit armor inside the crates.

Jump into the water and enjoy the reflections on its surface until you reach
a red container. Climb up the ladder on its left to get in and meet part of
the resistance...and a nice vortigaunt alien, powering a TV with its
electrical power. ^^ Get some of its power to strengthen your suit and break
some obstacles outside to enter the next area.

[The Railway]
Crawl through the rubble, watch a Barnacle eating a raven and witness an
execution. There's still a survivor in the canal on your right so haste to
him before it's too...ok, it's too late, no matter what you do. Position
yourself on the rubble and take down the executioner on the far left as well
as another one coming around the right corner. Get around the corner yourself
and run for the stack of crates. Crouch after a few steps to hide from the
machine gun and quickly enter the canal on your right. Kill a lone Combine in
Underground Station 12 to gain access to lots of suit energy and the com
showing how drastically the rebels are being attacked. Climb up the ladder,
shoot the explosive barrel and take care of any survivors before taking
control of the machine gun yourself.

There will be few waves of Combine and Sentry Drones coming from two points
on the lower level and from two on the upper level, but as long as your
aiming is somewhat good and as long as you concentrate on the Combine you
shouldn't be in for a lot of trouble. Once the normal enemies are defeated, a
police car opens fire with heat-seeking missiles, so quickly leave the
machine gun and keep moving to not get hit. In case you need it, there is a
health pak near the stack of crates you used to hide behind a few moments ago.
Shoot the barrel on the levelled ledge to your right to lower the platform.

Follow the ledge to a lambda symbol. There's some health behind the red car
wreck. Avoid the Barnacles, but shoot the last one before reaching the
daylight again, as it blocks the path out. Listen to the only survivor of the
nearby rebel station and enter another canal.

Are you in for some killing? If the answer's yes, then look up and try to hit
the two Combine guards as often as possible before they run off to the right.
Follow them underground into a water basin and watch out for the burning
explosive barrels they drop down once you go for a swim. Either stay at the
surface a bit prior to diving out of the way of the explosions or climb out
of the water to avoid the explosion. Then look up again and finally dispose
the two bad guys.
If you don't want to kill them and just want to get along peacefully, ignore
them completely and speed through the canal.

Leave the canal, shooting a few more enemies either by hitting explosive
barrels or by attacking them while they jump down. Crouch behind the van to
see some more barrels at a bridge. Shooting these prevents some Combine to
appear after a few more moments. Move on and quickly dispose two Combine
dropping down on the left and on the right. Use the crowbar to push a
harmless barrel into the tentacles of the Barnacles up ahead and quickly pass
by when they pull it up, expecting some prey. Then grab one of the explosive
barrels and feed it to the mass of Barnacles that comes next. Stay near the
other barrel and shoot the thrown barrel twice when it is pulled up, so it
starts burning and explodes right at the aliens. Afterwards repeat for the
other barrel and move on.

Don't get out of the canal just yet. Instead watch the explosive "treat"
falling down into the water ahead. This is a warning, so be on your guard.
Jump into the water, hiding behind the wooden wall to dodge another barrel.
Then peek around the corner where an explosive barrel near some Combine
couldn't possibly be placed any better. It creates a big chain reaction,
leaving behind only one Combine at maximum. Climb up the ladder ahead and
swim on, ignoring a barrel being dropped behind you on your way. Walk up the
ramp and hide behind the wooden poles to have a better position against the
two Combines entering the action on the bridge. Hop from platform to platform,
only retreating once to dodge a barrel, to reach just another canal, yay...

[First Act for the Helicopter]
Put some concrete blocks onto the left side of the seesaw to enable yourself
to use it as a path up to the exit. Yikes, a helicopter! You'll deal with it
for quite a long time and it won't be a pleasant time. Slide down and hide
behind a wooden board on the right until the copter's first burst is over.
Then to the closed canal entrance in front of you and as the third hideout to
the Barnacle on your left. Afterwards open the door nearby and enter the
building. See that lambda below? Climb down a ladder to some goodies before
moving on. Crawl through the shallow water, shoot the explosive barrel in the
place with the low ceiling and pick up some stuff. Now pick up another
explosive barrel to feed it to a few Barnacles. Its remaining pieces should
distract the Barnacles further down the ramp, but if you're too slow, just
grab a normal barrel as a distraction. Slide down and repeat the whole
procedure against two more packs of Barnacles. Leave the building and quickly
sprint around the left corner, because the copter opens fire again, without
leaving you any good place to hide.

[Manhacks]
You'll reach another small outpost of the rebels, only held up by a single
man. After a short conversation some manhacks break through the door. Either
use the crowbar to quickly destroy them and rescue your ally or (as he
actually serves no purpose to you) stick with the pistol and move backwards
through the corridors while fighting the manhacks. This takes longer and it
uses ammo, but it saves health. Afterwards climb up the ladder to find some
goodies. Move on and attack three manhacks through a girder door. Eventually
they will find their way to you above the door, but then they should already
be damaged quite well. Hit an explosive barrel around the next corner twice
to aid you against some more of those pesky machinery things.

When you see the daylight, don't exit already, but go on to find a few
goodies. Only then step out and kill two Combines up above. Hear those
manhacks coming? The best thing to do now is to retreat into the corridor and
to close the door. There are five manhacks around, but they can't reach you
now. Take your time and shoot them through the door. Then go out again and
enter the next corridor. Ignore the barrel for now and crawl through the vent
on your left. You have to face a manhack in here, but the loads of supply
crates at the end of the vent are well worth it. Go back and blow up the
barrel as a Combine has positioned himself next to it.

Drop down and move on until some Combines rope down. Give the one nearby a
headshot and retreat behind the small stone edge. Wait for the other two guys
to come by the explosive barrel to have an easy time against them. Pick up
the SMG they dropped and place the other red barrel where the first one was
lying. There's a narrow passage behind the barrel: Crawl through, pick up
goodies and kill your first zombie. Then crawl back out to see another
Combine being triggered to rope down. Luckily you have placed a barrel right
next to him. You know what to do.

Time for a dive: Search for the underwater passage in which you have to
surface once to refill your energy. Then follow the pipe to two Combines
roping down again and to a Sentry Drone. The easy way now is to walk up the
stairs (watch out for the Barnacle) and to hop onto the pipe from there. This
path might be easier, but it also makes you pass up on some good stuff. If
you want that, step outside and face two Combines and two manhacks prior to
jumping onto the pipe. No matter which path you choose, you have to walk
along the pipe, wait for the steam to pause, destroy a manhack in a narrow
spot and dodge some Barnacles. The best way to get through here is to quickly
grab the barrel around the right corner, let it be pulled up by the first
Barnacle and to hit it twice on its way up.

Break the boards near the lambda sign to reach another place in the outside.
Equip the pistol to quickly get rid of the guard at the truck up ahead. As
you do, the truck unloads some explosive barrels which you should blow up in
midair. This takes care of another Combine nearby. Equip the SMG and go
around the corner to trigger three Combines. Retreat and try to deal with
them one by one. The dark corridor you have to follow now, contains two
niches with items, but also triggering two manhacks. The items are worth it,
though. Afterwards go to the end of the corridor and retreat backwards. A
bunch of manhacks will follow you, allowing for a great use of your grenade.
Use the SMG to deal with the rest while still walking backwards.

The next room has some nice goodies, but you will need them. Crawl through
the vent and after a bout 3 to 5 seconds you better start a big chain
reaction with those explosive barrels to clear the room of loads of manhacks.
Destroy any remaining with your crowbar. Climb up the ladder, jump onto the
pipe, go left and drop down to a passage leading to a room with another big
pool of water. Don't open the supply crate yet, if you can take a bit of
frustration and if you want some suit energy. I'll tell you what I mean in a
few sentences. Drop down from pipe to pipe to find a valve pumping more water
into the two rooms. Now pick up the crate and carry it over to the first room
where four manhacks have spawned in the meanwhile (is "spawn" actually the
correct term for manhacks after all?). Lay down the crate while fighting them.
Then pick it up again, jump into the water, climb up the ladder while only
seeing it at the left end of your screen (or else you cannot carry the crate
while moving up), hop onto the pipe and place the crate at the bend on your
left so you can use it to reach the bar directly in front of you and the vent
behind it. There is only one single suit energy item in the vent, so decide
for yourself whether this is worth all the hassle (and don't forget to bust
open the supply crate).

No matter how you decide, you have to swim down into a tunnel and break some
boards underwater in the other room. This makes some objects float at the
surface so you can use them to get up onto the ledge leading to the next area.

[Radioactive Man]
Get up the ladder, dispose a Sentry Drone and mentally prepare yourself for a
rather difficult fight. Jump down behind the fence, turn right and run in on
a manhack while shooting your SMG at it. Continue to a dead end, turn around
and destroy another manhack. Shortly after two Combines rush in, so I hope
you have taken care of both manhacks before. Use the SMG on these four
enemies. Go on, jump up via the barrel and let three manhacks taste your
crowbar before nabbing some items. Up ahead are even more goodies you can
earn by distracting a Barnacle with a barrel. Climb up another ladder and
feast on the two lambda symbol spots before dropping down on the other side
of the wall (watch out, though: I once got stuck and squished in midair when
dropping down here).

Return to the daylight. This time around it is gonna last for a while. Stay
away from the radioactive waste and traverse it on the pipes for some items.
Then move on at the lower level and assist a rebel against two headcrabs. The
crate on your right holds an infinite amount of SMG ammo. The next section is
best dealt with by advancing slowly, watching for all those headcrabs to
unbury themselves. There are also a few zombies mixed in, but as you can
always go back to pick up SMG ammo you can shoot around as wildly as you like
to. Close to the end of this place (which seems to have been a living place
for some rebels) you come across an electrified cable (wait for it to swing
right before running past it on the left) and an electrified container which
seems to be more of a problem than it really is. Only the container walls can
hurt; standing inside of it doesn't do anything. So go through it and stay in
it when a headcrab missile crashes down. The headcrabs will jump against the
container, dying instantly. Hehe.

After a short walk you arrive at a hovercraft garage of the rebels. Board
your new vehicle and ride along the radioactive river up to a shut gate on
your left. Get out of the hovercraft near the headcrab missile ahead and kill
one of those aliens behind the stack of boxes. Then open the gate and drive
through to the next chapter. Look closely to see a supply crate in the liquid,
which you should break open by driving over it.

Kevin Johnston's Blog - http://www.300bucks.ca