
Others are a lot faster, and one breed uses organic weapons which you can use yourself. The lumbering insect-like Voltigore is one of them, meant to be an obvious fill-in for the Garg. In addition to most of the aliens we’re familiar with, Opposing Force introduces about ten new enemies. But in a brilliant scripted scene, Shephard just misses the last chopper heading out, and suddenly the player’s M.O. Not ten minutes into the game and the now-infamous order is received via radio: “Forget about Freeman.” The alien threat is too much, and all marines are ordered to pull out. This luckless marine got his head crabbed. And if you remember the original game, you’ll know that the marines are hopelessly outmanned and outgunned. It really does feel like you’re venturing into new undiscovered parts of Black Mesa during the alien invasion. Even though you’ll revisit a few places from the original, it doesn’t feel in the least like recycled material, but rather gives off eerie feelings of deja-vu. Opposing Force flows naturally alongside the main storyline, allowing you to catch subtle glimpses of events and locations from the first game.
The opening segment is every bit as creepy as that of Half-Life. Marine Adrian Shephard, now transferred to a special detachment known as the Hazardous Environment Combat Unit (HECU), and find yourself en-route to an undisclosed location via Osprey transport choppers when things suddenly go to hell.

Opposing Force lets you to experiencing the Half-Life story through the perspective of one of the grunts sent in to contain the alien invasion at Black Mesa, the ultra-secret research facility from the original game. Not as creative as its source material, but a great add-on nonetheless.
