Half-Life was a watershed moment for the first-person shooter genre, but it was a mod of the engine that ended up being its most enduring legacy. Yes, Counter-Strike: The game that launched a zillion online deathmatches, not to mention the popularity of competitive online warfare that continues to this day.

Counter-Strike can be seen as the Western counterpart to StarCraft, in that both games brought eSports from a geeky gamer pursuit into the big time of arenas, sponsorships, and gaming celebrities.

From 2004 to 2007, the Cyberathlete Professional League featured six FPS (Counter-Strike, Painkiller, Unreal Tournament 2004, F.E.A.R., Quake 4, and Halo) and only one RTS, Warcraft III. Fast-forward five years, and 2012′s Intel Extreme Masters dropped Counter-Strike from the roster, ending any FPS exposure at one of the world’s biggest eSports venues. Not only is that a blow to Valve’s perennial competitive entry, it’s a slap in the face to the entire history of competitive first-person shooters; a history that stretches back to the mid-1990s with Doom and Quake. How did the FPS become an endangered species in eSports?

Counter-Strike has evolved since it was first developed, from Gooseman and Cliffe’s original mod to the “official” Valve version, to the Source engine overhaul. But the biggest evolution is August’s release of Counter-Strike: Global Offensive. CS:GO will be released on PC, Mac, Xbox360, and PS3, but the initial promises of full cross-platform compatibility would never be realized. Due to the difficulty of synchronizing updates between desktop and console versions, only the OS X and Windows players will be able to share their online experience, while consoles are limited to matches between players on the same gaming system.

New gameplay modes, new weapons, and updated graphics will distinguish CS:GO from earlier iterations, but eSports aficionados will be more interested to see if it can retake some of the lost ground in the competitive genre. How likely is that? Much of it depends on how much Valve is willing to develop CS:GO to be as appealing to spectators as it is to the gamers; in other words, take the Blizzard approach, rather than the Call of Duty/Battlefield approach.

The Electronic Sports World Cup lists CS:GO among its seven games for 2012. It’s hard to draw too many conclusions from this, given that a few of ESWC’s games are not exactly household names (ShootMania and TrackMania, for example). Major League Gaming has not committed to CS:GO one way or another, but MLG never offered a Counter-Strike event even when the game was huge (preferring Halo and Call of Duty for FPS entries).

On the positive side, the ESEA League has never given up on Counter-Strike; except for StarCraft II, every major game on the site is a version of Counter-Strike (well, there’s also Team Fortress… but come on, close enough!). And even before the official release of Global Offensive, ESEA hosted a “Play with the Pros” CS:GO event on August 16, with the winners including pro gamers from the U.S., Canada, and Japan. That’s a very good sign that the FPS side of eSports is still alive and well, even if some of the biggest events don’t want to admit it just yet.

Stephanie Caldwell writes for CableTV.com. She is an avid reader, writer, and gamer from Salt Lake City.