Hi,i’ve read through the thread,many interesting theories.
Off:When i saw the lost episode with Richard,i was like WTF that’s the gman
On:
Here’s my theory:
The vorts were freed unintentionaly mostly.Gman could be an alien who’s world/planet/universe was enslaved by the combine.The combine had means of transportation to XEN.They learn about the existence of our universe when scientist started to enter XEN,and this way they might also be aware of human’s means of teleportation wich was somewhat better than theirs.Also XEN was probably controled by the Nihilath who might as well be a survivor of the combine asimilation,he escaped in to XEN,enslaved the local population and used it to protect XEN from the combine threat.
The combine used gman’s unique(maybe unique,maybe there might be others like him) as a rock to hit 2 birds.
1.Removing Nihilanth from the way.
2.Breaching into earth’s dimension.
At the end of hl1 gman states the boder world xen is in OUR control for the time being,thanks to you…
While the combine did not exist in hl1,it is still canon and hypotesis can be made that OUR refered to the combine.
Afther the Nihilanth’s demise,the portal storm allowed the combine to enter Earth’s dimension.Gman,could from the very begining be acting in his own intrests,knowing that the combine have to way to leave a dimension after entering it,used earth as a trap for the combine advisors.
On earth gman acted after his own will,and he offered gordon’s services to the vorts/ressistance.After the events of hl2 he considered that humans were in no longer need of Gordon’s services.That’s when the vorts released gordon,this being like a payback since Gordon liberated them.By the course of gordon’s actions gman maybe realised Goron’s great potential againts the combine so that’s why he no longer tried to catch gordon in statis.
I know long post,and a lot of mistakes,sorry my english is not perfect