Not long after Gordon ducks into the underground hallways next to the train yard, he hears a woman crying for help nearby. As he rounds the corner, he sees two Civil Protection officers, one of them beating up a citizen, and the other restraining his female companion. Gordon makes short work of them, but rather than thank him the woman sternly remarks that he's now a target for the CPs and should get moving.
After dispatching a few more officers, Gordon emerges from the underground passage to see the Citadel once again, with dozens of Combine Scanners being sent out from the structure to search for him. More cops descend on his position not long after, with one of them launching a signal flare to summon backup, so Gordon fights his way through them while navigating along the nearby train tracks, dodging the Combine's Razor Trains all the while. He comes across a walkway from which he can jump into the canals below, which he promptly takes advantage of to momentarily escape the heat.
One brief swim later, Gordon finds himself in front of a boxcar situated in a dried-up section of the canal. Dropping inside through an opening at the top, he finds the boxcar is actually an improvised shelter being used by a runaway citizen and his Vortigaunt companion. The citizen introduces himself as a lookout for the Resistance's Underground Railroad and tells him that the main station is just around the corner, and has the Vort charge his suit before sending him on his way.
As Gordon approaches the station, he hears a group of people begging for their lives, and turns the corner to see several rebels lined up against a wall get shredded by gunfire. Turns out Civil Protection got to the station first, and they've set up an emplacement gun to watch over the whole area, so Gordon flanks into a nearby drainage pipe in order to take out the officers manning the gun from behind. Just before climbing out he hears on a nearby radio that Civil Protection is targeting all of the other stations and filling the underground with "manhacks".
After taking control of the emplacement gun and fighting off a backup squad, Gordon continues on his way. A rebel hiding in a pipe encourages him to seek help at the other stations up ahead, while insisting she'll stay behind to keep the main station alive.
Several CP confrontations later, Gordon finds himself face-to-face with his first big adversary: the Hunter Chopper. His meager arsenal isn't nearly enough to bring this helicopter down, and its powerful pulse cannon spells trouble, so he ducks into another underground passage to hide from it. It's here that he comes across another smaller station with a lone rebel watching over it. He urges Gordon to get a move on before the Manhacks find them, but right on cue these flying buzzsaws burst in, and Gordon takes it upon himself to help his acquaintance fight them off.
The rebel thanks Gordon for his assistance and offers some of his supplies before he heads off. Gordon continues on his journey, fighting off more Civil Protection and the occasional group of Manhacks, and eventually comes across Station 6, a shantytown located at the edge of the canals. A citizen next to a radio recognizes Gordon and mentions that he was expecting his arrival, at which point Alyx calls in over the radio to inform him that Gordon is to be lent an airboat to help him travel the rest of the way to Black Mesa East.
As Gordon enters Station 6 proper, a mortar-like shell flies in and crushes two rebels right in front of him. The shell then opens up and out pop some Headcrabs; it would seem that the Combine is weaponizing the creatures to attack the Resistance. Gordon ventures further into the ruined station as it comes under fire from more shells and comes across several Headcrab Zombies. After getting past them and entering a culvert just outside the camp, he comes across a rebel who's fueling up a makeshift airboat. She tells Gordon to seek further help at an old barn up ahead dubbed Station 7 and wishes him luck in dodging Civil Protection out in the open water, then opens the gate to let him and the airboat through.
This chapter contains examples of:
- All There in the Manual: Many of the refugees encountered in this chapter are named, but only by internal files or the Half-Life 2 Prima Guide.
- The man in the boxcar is named Joe.
- The woman hiding in the pipe at the edge of the main station is Mary.
- The rebel who Gordon can help fight off the first Manhacks is named Matt.
- The guy next to the radio at Station 6 is named Al.
- The rebel who fuels up the airboat is named Arlene.
- Antepiece: As the first chapter with actual gameplay, a fair few mechanics are introduced in a gradual and comprehensive way. As described this article
, there's a part early in the game where you need to push some barrels aside to move forward; doing so causes them to roll down a slope and get caught by a Barnacle. This cues the player into learning that Barnacles will snare physics objects, testing their knowledge when they're given a similar situation with an explosive barrel to kill multiple Barnacles at once.- Exploding barrels. First you simply walk past them. Then you fight off some Civil Protection enemies standing next to them, and get ambushed by a flaming barrel pushed down a flight of stairs. Later on, a pair of CPs use a bunch of explosive barrels to try and flush you out from the drainage, introducing the concept of diving into water to avoid getting blown up, which shows up a couple more times in the chapter.
- Barnacles are introduced here as well. The first one swallows up a crow as it tries to fly away, showing off exactly what the creature does. Then you're forced through an area where you have no choice but to either kill the Barnacles in your way or get grabbed by them. Then some time later you push through a row of barrels to get inside a drainage ditch, and said barrels roll down an incline into a crowd of Barnacles, demonstating that they can pick up physics objects as well. Combine this with your prior knowledge of explosive barrels, and you've got a surefire way to take care of Barnacle groups with ease...
- Monster Munch: The Combine start headcrab-shelling the outskirts of City 17 to try and kill Gordon. At one point you get to watch as a headcrab latches on to a civilian's head and turns it into a zombie (or Mercy Kill him before he gets assimilated, whichever floats your boat).
