=Half-Life: Opposing Force=
I'm just going to come out and say it. I'm an Op4 fanboy. Always was. From the day it was announced to when I finally got my hands on it and beyond. I hung out on the official Sierra forums a lot and after awhile I started collecting every scrap of info about Op4 and putting it into a huge post. This got the notice of one of the Gearbox members who posted there. He asked me if I would be willing to maintain a FAQ for Op4. Being a 14 year old with no life, I absolutely agreed.

Anywho, enough of that crap, Op4 was considered by many to be as revolutionary to expansion packs as Half-Life was to first person shooters. Ran than just add a bunch of new missions for Freeman, Gearbox went into a very different direction. New character, Corporal Adrian Shephard, from the opposite side of the game who's adventure takes place at the same time as Freemans. By making the main character a soldier, it opens up a lot more of the Half-Life universe to the player. (Though it sort of acted in opposite to the dehumanizing effect Half-Life was trying to achieve :D)

In addition, Gearbox added a SLEW of new weaponry (and didn't fall into the trap of having to provide the player with EVERY previous weapon in the game, whether it made sense or not, so no Hivehand, tau cannon or gluon gun.) in the order of 8 new weapons to the original 14, and quite a few new capabilities for the main character. Being a corporal, Shephard is able to command up to five soldiers at a time, use radios to call in reinforcements and climb ropes. The angle they used really allowed them to expand the abilities of the Half-Life game. The amazing this is they got all this done 1. On time and 2. In about a year. Incredible.

Recently I've noticed a lot of anti-Shephard and anti-Gearbox sentiment throughout the Half-Life community. Oh well, sucks for them. Opposing Force was a great game. It did some things better than Half-Life, some things worse, but ultimately it's a very worthy successor.

-Boot Camp-
I really got to give them credit on this one. They took a concept from Half-Life 1 and just ran with it to a touch down. Complete with references to Full Metal Jacket and other famous army movies, the atmosphere hear is great. Interesting fact, IIRC, the guy who voiced the Drill Sergeants is none other than Jon St. John, the voice of Duke Nukem!

Man, the Gman is just everywhere. Here in the Boot camp we see him looking out from a window high in the courtyard.

The PCV is kind of interesting. I wonder if its based on the HEV design. If I ever remade Half-Life, I'd make sure to retcon the PCV onto the soldiers in that game, making them into sort of mini-mini-bosses. (Imagine taking on 4 marines with ~200 health instead of the normal 100.) Or maybe just use PCV's for squad leaders.

Nightvision is another situation where Gearbox took what was in Half-Life and did managed to do it again without it just being a retread. The NV fulfills the same function, but works and looks differently, making the experience more unique.

The obstacle course is pretty fun: refresher on the hazard course + drill sergeant taunting you. The ropes are pretty interesting: not something we've really seen since. They're do feel a little off, but any attempt to give the player more options and give the levels more variety is welcome.

I like how in the firing range takes your weapons away after your done with that section. :D Also like how you can get court marshaled for shooting the sergeant. During the command portion, it's again apparent how Gearbox took what Half-Life had and tried to expand it into interesting places. Instead of using scientists for their retinal scans, you use a engineer to just cut the door open, and instead of just using a wall mounted health dispenser, you have a medic heal you (or your allies).

The radios are an extremely nice touch, taking a familiar element of Half-Life and making it a useful tool to the player.

-Incoming-
They pretty much just combined the tram ride and the accident into a single event, which I think was a smart move. We get a familiar feeling without it being a long, boring retread. The banter of your teammates is great. :D

Also nice is the first of many “crossovers” with Freeman's journey: the cliff area from Half-Life seen outside of the Osprey. Nice of Gearbox to even set things up so your likely to look out the window when it happens. (Watch out Goose 7, it's getting kind of tight in here)

-Welcome to Black Mesa-
As we run through the early areas, we can see some of the new zombies. I wish this had been in the original, but such is life. Also here are the new cleansuit scientists and Otis security guards, both added to give more variety to the denizens of Black Mesa. You find the your first weapon nearby, the Pipe wrench was a nice choice, though the reason I read for adding it was to give players a quit way to destroy crates :D “Optical Mirrors are Fragile” continues the tradition of sign puzzles. :D The gman returns, seen talking with a security guard, before wave his hand and walking off.

Outside can be found the combat knife, which is kind of interesting as it was added late in development because Gearbox actually had extra development time. How often do you hear about that kind of stuff these days? :)

The desert eagle is nice, but horribly overpowered with it's super accurate secondary fire. One thing I sort of don't like about Op4 is how all Barny's have Glocks, all Otis's have Desert Eagles and nobody has shotguns or whatever. More variety in the weaponry the security guards have would have been cool.

The room where everything blows the hell up was cool when I first saw it, but it seems kind of “forced” now. It does provide the interesting part where the Gman appears and saves your sorry ass though.

The parts where you come across areas from the HL1 tram rides are pretty cool. Back during Op4's development, there was mention that you'd be able to control the spider walker mechs at some point, but that just turned out to be shooting boxes so it could move again. One of the few times I was disappointed with Op4.

-“We are pulling out!”-
This is the first appearance of Race-X: the OTHER aliens used to explain why there's a whole bunch of new critters in Op4 which Gordon never saw. The story behind Race-X is that they're another telelporting race, and all the activity at Black Mesa drew their interest: so they began abducting BMRF personelle (as seen in this chapter) and Xen lifeforms (not seen in the game).

The Barnies in Op4 all have voices that seem “off” and it wasn't until after Blue Shift and during Decay that they got back to the good old HL1 style.

When you finally meet up with your squad, you get to hear the famous “Cooper? Johnson? Forget about Freeman, we are pulling out and commencing airstrikes..” speech as well as the guy who made it. The voice is SPOT ON which makes it especially cool. So Adrian is about to flee Black Mesa and not die a horrible death. Apparently Gman doesn't like that and he prevents you from fleeing. Rat bastard. They really made you hate the Gman in this one. :D

-Missing in Action-
The Gonome is an interesting monster: Essentially a zombie further along in mutation, able to throw acid, eat or generally tear the hell out of you. There's another “warning sign” puzzle here. “Do not obstruct flame” + “Danger: Explosives” = Progress!

The Pit Drones are huge pain in the asses: Lots of health, fast and do extremely good damage. They come in packs and sometimes can shoot spines from their heads. Damn this game amped up the difficulty.

-Friendly Fire-
Heh, Freeman as the “Employee of the Month.” Anywho, this is where the huge, pain-in-the-ass, Black Ops first show up. Now that the order to pull out has happened, they're turning on the military, providing the player with EVEN harder opponents with that super awesome Half-Life AI. Just what we need: faster, deadlier marines. I guess they had to provide some kind of advanced enemy if they were going to give you allied soldiers and walking health stations. :D We also hear talk of “the package” for the first time.

This is also one of the few times Alien Grunts show up in the game: the rest of the time it's just slaves or fauna.

-We Are Not Alone-
This is the big crossover point, as it is where you actually encounter Freeman, just as he jumps into the Xen portal. You get to see, and deal with the aftermath and then get sent to Xen, where you find the Displacer: an unstable, self-contained teleportation unit. Using it here sends you to the Hazard Course where you can snag some health.

-Crush Depth-
Ah, the obligatory underwater type area. Isn't this supposed to take place in the desert? The Shock Trooper first appears as an enemy in this stage, and killing him rewards you with an electrical based Shock Roach weapon.. The Shock Trooper runs off the same AI as the soldiers and Black Ops, to hopefully avoid the problem with Half-Life 1 where people missed fighting the soldiers towards the end of the game.

-Vicarious Reality-
Best chapter title ever. This shows just how extensive Black Mesa's knowledge of Xen was: a fully function Xen biodome facility. As you work through it, you get attacked repeatedly by more and more Race-X, including the living tank that is the Voltigore.

The spore launcher (And its interesting method of ammo gathering) is actually a infant Shock Trooper (At least according to it's filename baby_strooper), which makes sense as the adult can regurgitate spore grenades as well. I wonder how Black Mesa got ahold of the infants and the spore spawners…

There are a few things about the Barnacle. First of all, “Walter" is a reference to the comical Planet Half-Life character Walter Bennet. Secondly, here's an interesting difference between HL1 era and HL2. In HL1, Barnacles would only catch organic stuff, but in Half-Life 2, thanks to the physics system, they'll catch anything. The barnacle grappling hook only attaches to organic material, which allowed Gearbox to exercise control over when and where the player could use it.

Strangly I have encounted a bug on this run through that forced me to noclip to the end of the chapter. Oh well.

-Pit Worm's Nest-
After falling into a Star Wars-esqu garbage compactor, Adrian is released by the Gman who returns again. This series of chapters is pretty much a straight take on Blast Pit: Navigate around the giant creature to activate stuff that you need to kill it to proceed. While it's pretty blatently “that was cool in HL, so lets do it again,” it also allowed for a big in-joke with the steam valve and the pump gearbox. :)

The worm itself is pretty cool. It shoots eye lasers and slashes at you with it's huge arms. It's design is reminiscent of the Shock Trooper, though it's name would imply that it's related in function to the Pit Drones. I kind of wish all of Race-X had a unified visual theme (insectoid with the central eye) instead of being another mish-mash of various critters like Xen was.

-Foxtrot Uniform-
Heh, just in case you don't know, Foxtrot means “F” in military lingo and Uniform means “U.” Adaquatly named chapter. From the tons and tons of black ops fighting within a heavily explosive laden area, to the infamous tunnels filled with Voltigores and infinitely spawning Pit Drones, it lives up to the hype, and then tons of Race-X. This is probably the hardest area in the entire Half-Life series, IMO. Makes the part in Nova Prospekt look like cake.

At the end of this chapter, we return to the dam from the original game where a gargantuan is tied down and the Gman is talking on a cell phone.

-“The Package”-
This episode features one of most controversial Gman moments in Half-Life history: After disarming the “package” (A nuclear bomb that the Black Ops were planning on using to destroy the facility) the Gman waits until you're unable to return, and rearms it.

-Worlds Collide-
And it seems we have entered the Crate Capitol of Boxland. Seriously, how many warehouses does Black Mesa have? Anywho, this place is filled to the brim with Black Ops, and then Race-X. Luckily it's a lot easier than Foxtrot Uniform.

The Geneworm looks a lot like a tentacle and supposedly has the genetic code for the entire Race-X. Killing it is an exercise in repetition. Shoot the smaller weakpoints so it reveals the big weak point, shoot the big weakpoint to damage the critter, kill the shock trooper it spawns, heal the health in the x3 healing pool nearby and repeat 4 times.

-Conclusion- So, we kill the geneworm and get our regularly scheduled meeting with the Gman. Unlike Freeman, though, Shephard the Gman's employers do not want to hire him; or even let him live, however the Gman intervenes and argues to keep Shephard safe, if not let him go. This shows that the Gman isn't a slave to his employers, and it also shows that he has wants outside of whatever his job is. Plus we get that line about “people adapting and surviving against all odds” reminding the Gman of himself; though that might have just been sarcasm.

Status: Detailed; further evaluation pending. Still pending in fact, but there's a slight possibility we could see something in Episode 4.