I finished my second run-through of HL2, and there was something I noticed in the final sequence when G-Man appears after you blow-up Breen.
When he talks to you, he makes strange noises when he inhales in between sentences. They are gutteral and drawn out, like something an alien would do. The only human that would sound like that is someone with emphysema. Couple this with his dry and monotone language, and the writing is on the wall...
This makes me think that GMan is some sort of alien in human form. I know this idea has been proposed already, but I just wanted to give it some more merit to back it up.
When he talks to you, he makes strange noises when he inhales in between sentences. They are gutteral and drawn out, like something an alien would do. The only human that would sound like that is someone with emphysema. Couple this with his dry and monotone language, and the writing is on the wall...
This makes me think that GMan is some sort of alien in human form. I know this idea has been proposed already, but I just wanted to give it some more merit to back it up.