HALF-LIFE: BLUE SHIFT / Valve / PC
Blue Shift was originally designed as a bonus scenario for the scuttled Dreamcast port of Half-Life. It was reworked instead into this add-on, the second and last commercial "extra levels" release directly from Valve. As it was originally meant to "plug in" to the original game without the presence of other add-on Opposing Forces, the weapon selection and the (thank god) rope-jumping sequences are gone from this one, and the weapons and items more closely resemble Gordon's original inventory.
You play as a generic Barney at Black Mesa during Gordon's events. Apparently you actually share a shift starting time with Gordon as you see plenty of him as you go to work. We've been through this twice now so you know the drill - "resonance cascade", aliens from another mother beaming in and laying waste, etc. Barney simply tries to survive and escape. To give you an idea of game length, however, as you start out you're seeing Gordon taking the tram to work, but in the game's ending you're seeing an event from about halfway through Gordon's journey. Like Opposing Forces it's about 5 to 7 hours of gameplay versus the original game's 10 to 15.
The game is competently designed, and I actually enjoyed it much more than Opposing Forces due to a relative dearth of obnoxious jumping puzzles, the aforementioned lack of bullshit rope-swinging, and more of a focus on firefights with the always devious Marine squads. However, unfortunately, it's pretty much the same old tune on the same old fiddle for yet a third time - same old crumbling Black Mesa environment, same old enemies, etc. There's also no multiplayer component whatsoever - no new maps, no nothin'.
The big selling point for this one is not really the game itself, however, but the included HD Pack, which upgrades Half-Life and all other mods to the improved textures that were to be used in the Dreamcast version. Apparently there's some hinkiness if you get it through Steam, however, where their version interferes with other mods because it doesn't include expanded animations used in the original retail release of Blue Shift or something.
* Gameplay Videos