Gamespot reports that Valve has released “Half Life 2: Lost Coast” on their Steam client. Gamespot sums up the gameplay:

If you’ve played through Half-Life 2, the gameplay in Lost Coast isn’t going to set the world on fire. You fight your way up a sheer cliff face, trading fire with those pesky Combine soldiers every step of the way. You’ll occasionally have to deal with some of the more vicious sorts of headcrabs, and at the end you’ll have to bring down a Combine gunship with Gordon Freeman’s trusty rocket launcher. You’ll have to solve a couple of light physics puzzles as well, which we won’t detail for the sake of preserving at least a little of the surprise. You’ll even get to talk to an old man at the beginning of the level, who provides you with the impetus to head up into the hills and engage the Combine in the first place.

Lost Coast also features new High Dynamic-Range Lighting, which is a significant improvement of graphics. Caveat Emptor: Valve says that the system requirements of this game are “very high”, meaning that this game may not run well, or function at all, on a computer that was able to run Half Life 2. Luckily, the Steam client does prompt the user if his PC is not up-to-snuff.