History Recap / HalfLifeUnforeseenConsequences

* MooksButNoBosses: For this chapter, none of the really big aliens have shown up yet.

* BodyHorror / FaceFullOfAlienWingWong: Introducing the headcrabs, small but aggressive aliens that attack by leaping onto the heads of human prey, latching on, [[PuppeteerParasite and converting them into mindlessly vicious zombies.]] Worse, the zombies physical forms seem to mutate, such as their fingers extending into claws.

* {{Foreshadowing}}: Very subtly. Gordon passes through the "Coolant Reserve Facility", implying that there's a reactor around here somewhere, despite Black Mesa being powered by a hydro-electric dam. [[spoiler: This sets up the Lambda Reactor that powers the teleporters]] in Chapter 14.

* SidetrackBonus: In the Coolant Reserve, there's a side area with a locked office that you need to bring the nearby hiding scientist to in order to open it. This office is the first opportunity in the game to pick up some Hand Grenades.

With Black Mesa in ruins and strange, dangerous creatures popping into existence left and right, Gordon is tasked by the surviving scientists with heading to the surface to get help. Unfortunately, the tram has been destroyed, necessitating that Gordon find a different route through the facility by going through the Coolant Reserve sector that resides next to the Anomalous Materials lab. Along the way, Gordon comes into contact with the strange and hostile life forms and being forced to arm himself to survive.

With Black Mesa in ruins and strange, dangerous creatures popping into existence left and right, Gordon is tasked by the surviving scientists with heading to the surface to get help. Unfortunately, the tram has been destroyed, necessitating that Gordon find a different route through the facility, coming into contact with the strange and hostile life forms and being forced to arm himself to survive.

* AliensAndMonsters: ''Everywhere.''

* ToServeMan: It's unclear about the Bullsquids, Houndeyes and Slaves, but Barnacles and Zombies seem to devour humans without hesitation.

* MysteriousWatcher: The guy in the suit doesn't seem terribly worried about all the horrors running around. [[InvisibleToNormals Nor do they seem to care about him.]]

* BodyHorror / FaceFullOfAlienWingWong: Introducing the headcrabs, small but aggressive aliens that attack by leaping onto the heads of human prey, latching on, [[PuppeteerParasite and converting them into mindlessly vicious zombies. Worse, the zombies physical forms seem to mutate, such as their fingers extending into claws.

* BodyHorror / FaceFullOfAlienWingWong: Introducing the headcrabs, small but aggressive aliens that attack by leaping onto the heads of human prey, latching on, and converting them into mindlessly vicious zombies. Worse, the zombies physical forms seem to mutate, such as their fingers extending into claws.

* BodyHorror / FaceFullOfAlienWingWang: Introducing the headcrabs, small but aggressive aliens that attack by leaping onto the heads of human prey, latching on, and converting them into mindlessly vicious zombies. Worse, the zombies physical forms seem to mutate, such as their fingers extending into claws.

* BodyHorror/FaceFullOfAlienWingWang: Introducing the headcrabs, small but aggressive aliens that attack by leaping onto the heads of human prey, latching on, and converting them into mindlessly vicious zombies. Worse, the zombies physical forms seem to mutate, such as their fingers extending into claws.