The Hidden - HalfLife Mod

http://www.hidden-source.com/

Dude, this mod rules! You see, it's like you're in a horror movie, where everyone plays as a squad of Red-Shirt mooks, except for one guy, who gets to play as this awesome mutant guy with PERMANENT STEALTH as well as super-strength and speed and wall-clinging and all that kinda thing. Whoever kills it (I think whoever does the most damage) gets to play as The Hidden next round.

It's a free mod if you've got Half-Life 2 on Steam, and it gets downright freaky, which is awesome! If you've ever played Alien vs. Predator 2, you'll probably notice what The Hidden is inspired by. So let's get in there and start murdering each other!

I used to play this quite a bit when I first got HL2. It gets pretty intense if you've got a good team. I remember being pretty good as The Hidden, too. I might try playing it if people are interested.