I'm at Ravenholme now. What an awesome level.
Anyway, I wanted to discuss the story, or possible story, up to this point. Now I'm sure someone who has gotten further will chime into this thread to give more details, so everyone be careful of spoilers, even me.

However, up to this point in Ravenholme, I have a couple of feelings:
1. Gordon Freeman himself doesn't know what's going on. With the strange intro to the game (G-Man standing amidst streaking stars talking about waking up), I believe that:
2. Gordon somehow was time warped between HL1 and HL2. I have a feeling that for him, mere minutes passed between the two events.
3. I believe that as the player is discovering new backstory, so is Gordon.
4. When you first get to meet Vance, he says something to the effect of "You haven't changed at all, Gordon. How do you do it?"
So does anyone have any other theories?
Note, this thread is more for people who haven't finished the game yet. If you have, and know the whole story, please don't spoil it entirely
