Did you know there's an official slice of the Half-Life saga that never found its way to PC? Decay was a bonus game mode in the Playstation 2 port of the first Half-Life, much as Blue Shift was supposed to be the exclusive extra bit in the ultimately canned Dreamcast version. But while the latter saw its own PC release (replete with the at-the-time ace High Definition pack) and can be had to this day from Steam, Decay seemed damned to dwindle into olden console game obscurity. Oh, the irony of its name.
Which is odd and sad, as it was developed by Gearbox and is, to the best of my knowledge, the only official attempt to make something other than a straight FPS out of the Half-Life series. Fortunately, a Ukranian team have painstakingly recreated Decay as a free mod for the original Half-Life, even grabbing the original sound files off the PS2 disc (hope they don't run into any trouble for that) - which means new voicework from the chaps behind Barney, Kleiner et al, plus a couple of new characters, so this really does feel like Official Half-Life. More importantly, it's your first and only chance to get chatted up by Barney. Well, unless he has an ulterior motive behind that drink he keeps promising to buy Gordon.
It is an FPS, and recycles big old chunks of Black Mesa, but first and foremost it's a co-op game - and that's still the case when you're playing it on your own. It's very much in the Lost Vikings/Project Eden mould - alternately guiding multiple characters through the levels and switching between them to aid each others' progress. This kind of puzzling's pleasing enough by itself, but doubly so when you're doing it in Black Mesa, surrounded by those comfortingly familiar characters -and sound samples. It's even plugged into the core story: you're playing as lady scientists Drs Cross and Green (which do you fancy?), who are helping set up Drs Kleiner and Freeman's Resonance Cascade experiment from another part of the complex. Remember this wee fella?
In Half-Life, it emerges magically from a hole in the ground. In Decay, you're the lab assistant that pushes it into place, ready for clumsy old Freeman to accidentally trigger the end of the world with it. Sure, there's a certain shoehorned-in, fan fiction element to it, but it does an ace job of blending original dialogue/events from HL - you get to hear the whole "it's probably not a problem... probably" spiel all over again - with new words and happenstance. It's the Back to the Future 2 thing: witnessing familiar events from a new perspective.
It's not up there with the HL saga's finest moments, but it's certainly a strong one, most especially because it adds something truly different to the formula rather than simply retreading or honing. Plus, being back in Black Mesa calms my soul. It reminds me how much I prefer HL1 to 2, and I still hope we'll see an official return to that sort of environment and setpiece at some point.
So it's fantastic to have this short but sweet lost Half-Life episode on PC at last, and it even has something the PS2 version didn't - online play. While it's surprisingly effective as a character-switching solo outing, really it's designed for co-op play, each of two players controlling one of the lady-docs rather than having to do all that stop-start bodyswapping. I played through Decay in split-screen co-op on PS2, but each player at their own PC is a far more elegant way to do it. That said, it's a shame there isn't any split-screen in this version, but it seems a minor sacrifice. Also there are some stilted animations, and I suffered a couple of crash bugs, but for the most part it's a near-perfect recreation of PS2 Decay, only a whole lot slicker to play thanks to mouse and keyboard support.
While I don't know to what extent the modders have made this from the ground up or have been able to simply recycle existing files from the PS2 disc, they've been at this for a good three years, so it's clearly been a mammoth undertaking. I'm dead chuffed it's finally seen the light of day, as otherwise Decay was in serious danger of being lost forever. The entire HL saga is restored and complete at last.
Download Decay from here. It only works with classic Half-Life, not the futile Half-Life Source, I believe, but perhaps someone will mod the mod.