Warning Heavy Spoilage!!!
So it basically goes like this:
- The Combine work for the big spire structure know as Xenohardrine and are a combination of Human / Alien and cyborg.
- The Humans are allied with the Class 2 Aliens not seen in HL1 (first contacted when the first transformational experiments started) and we are all at war with the Class 3 (headcrabs and shit).
- The Human and Class 2 alliance started construction on the big spire structure know as Xenohardrine that is designed to engulf a planet and imprison it's whole population. This is then accidentally unleashed into City 17 (apparently City 17 is a research facility).
- Black Mesa was a research program devising a way to get the big spire thing through to the Class 2 aliens homeworld, but that accident at the start of HL1 placed it in City 17.
- The administrator (the guy that ran Black Mesa and who is the Class 2 alien's ambassador) has called Gordan to destroy Xenohardrine's core.
- If the Xenohardrine is not stopped it will form a massive prison over the earth enslaving the entire planet.
- Alex dies at the end.
