Race X is a mysterious alien race appearing in the Black Mesa Research Facility late in the Black Mesa Incident, a few hours before Gordon Freeman teleports to Xen. They serve as one of the main antagonists of Half-Life: Opposing Force.
Race X consists of several alien species, ranging from average to large, originating from a homeworld residing somewhere beyond Xen. Shock Troopers make up the primary work force and military component of the race. They are said to employ or subjugate other aliens to serve their agenda. In combat, they use their own weapons, such as the parasitic Shock Roach, as well as their natural defenses, such as toxic spores or claws. They have mastered teleportation technology as they managed to develop it as an innate ability. Shock Troopers make free use of this strength to teleport in and out of battle at will and to bring in Pit Drones and Voltigores for support. However, they were not particularly well adapted to Xen. Of note is that Xen and Race X portals present a striking difference in color: while Xen portals are green-colored, Race X's are purple-colored.
Race X was attracted to Black Mesa by the Portal Storms resulting from the Resonance Cascade. They utilized their teleportation skills to discover Xen and began using the rifts between the borderworld and Earth to quickly establish a presence on the planet. The personnel in the facility were surprised by the invasion of this previously unseen force as suggested by a scientist upon witnessing a Shock Trooper, proclaiming that he has "never seen that species before." Hence, an "X" was used to denote the race's unknown origin. Race X creatures act independently from Xen units and are not participants in the conflict between the Combine and Nihilanth's forces. Instead, they act motivated by a biological function, intending to set up Gene Worms that would assimilate the planet's natural resources for their own needs. This plan is brought to a halt when Adrian Shephard defeats the initial Gene Worm attempting to emerge from an alien gate powered by Sprites, thus ending Race X's invasion.
 Behind the scenes
While collaborating with Gearbox Software on the development of Opposing Force, Valve Software writer Marc Laidlaw wished to use the expansion to elaborate on and reveal additional insight into the series' plot. In particular, he wanted to show "that the rift between Earth and alien worlds was much wider than just Xen, that there was a much wider community of other things out there in the universe". Gearbox desired to develop the expansion's gameplay beyond Half-Life's already familiar enemy types without interfering with what Valve had already established. As such, Laidlaw worked out a domain with Gearbox designer and writer Randy Pitchford that permitted the existence of other alien species in the game's universe and would allow the Gearbox team the freedom to come up with a set of creatures "that would create gameplay they knew how to make." This ultimately lead to the creation of Race X as "it made sense that a rift to a dimension other than Xen could have opened up to let other creatures in". Laidlaw has stated that Race X does not figure at all in his thinking about the Half-Life and Portal universe. He also suggested that if Gearbox had kept making games set in the Half-Life universe, more about Race X could have been revealed.
Most of the Race X creatures were designed by Gearbox artists Stephen Bahl and Brian Martel. Bahl wanted Race X to be bug-like in appearance, taking inspiration from insects, in order to make them distinct from the existing Xen aliens. Their relationship with Xen creatures was intentionally left ambiguous, hence the two forces are never seen interacting with one another in the game.
 List of appearances
- Half-Life: Opposing Force (First appearance)
- ↑ Stephen Bahl biography on Gearbox Software's official site (archived)
- ↑ 2.0 2.1 2.2 2.3 2.4 Stephen Bahl as quoted in the Marc Laidlaw Vault on the ValveTime.net Forums
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 Audio Interview with Gearbox Software on Run Think Shoot Live (November 3, 2012)
- ↑ .plan file of Brian Martel on Blue's News (September 7, 1999)
- ↑ 5.0 5.1 5.2 5.3 Half-Life: Opposing Force Prima Guide
- ↑ 6.0 6.1 6.2 6.3 6.4 About Race X in the Marc Laidlaw Vault on the ValveTime.net Forums
- ↑ 7.0 7.1 7.2 Randy Pitchford as quoted in the Marc Laidlaw Vault on the ValveTime.net Forums
- ↑ 8.0 8.1 8.2 8.3 Game Spin: Half-Life Expansion Gamecenter (June 18, 1999) (archived)
|Retail||Aperture Science · Black Mesa · Black Ops · Combine · Hazardous Environment Combat Unit · Race X · Resistance · Xen|
|Cut||Central Intelligence Agency · Agents|
|Creatures||Gene Worm · Pit Drone · Pit Worm · Shock Trooper · Sprite · Voltigore|
|Weapons||Shock Roach · Spore Launcher|
|Technology||Teleportation · Transportation · Weapons|