Half-Life 2 SP Hidden Lab Map

wiped out by millions of aliens... no one had ever seen this secret weapon, it was told that it could wipe out the entire base if triggered. 3 years after the Lab was destroyed, Combine soldiers discovered the lab was barricaded up and found a human, they found a parasite of his head, the combine soldiers got worried and rushed outside while under attack and locked the door to the Lab and never returned. 8 years after the combine soldiers discovered the lab; one brave soldier was very keen to find out what had happened in the lab and what he was inventing, he also knew the scientist very well so he had clearance to the lab...
Deep below the ground on the side of a cliff, a scientist was working on a secret weapon to destroy the aliens before they discovered the research lab, during this invention, he was discovered and