It would be based in an older complex than black mesa. The secter your working in is trying to extract the near limitless energy from a strange crytal on xen.
However the xen lifeforms didn't like haveing there crystal stolen so force open a small rift and take it back.
Haveing done this they take the chance to force it open wider and invade the labs. They also invade the small city that was built on a large xen platform as a teleport "relay" station and for studying the xen lifeforms.
Later on when the black ops come the millertry being on the "to kill" list make peace with the lab workers to fight there common emenys and get out alive.
I have done some work but need some help mainly in the mapping (cause theres a lot of it) area. I also need a voice acter befor I can complete the maps I started.
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