The best possible test subjects, the likes of Olympians, astronauts and war heroes were first chosen.

All of this was not done legally, going by the posters telling workers to alarm if they were to see any sort of journalist, police or workplace controlant. Throughout the late 1940s and the 1950s, Aperture Science would begin its comprehensive testing and research practices. Cave Johnson purchased a large, abandoned salt mine in Upper Michigan in which Aperture Science's Enrichment Center would be built however, there was at least one alternate location in Cleveland, Ohio. While this was initially done to make their shower curtains sound more hygienic, the company's focus would indeed soon shift to actual science. In 1943 the company's name was changed to 'Aperture Science Innovators'. Aperture Fixtures was primarily dedicated to the manufacture and distribution of shower curtains – a low-tech portal between the inside and outside of a shower – with Cave Johnson winning the 'Shower Curtain Salesman of 1943' award. For example, both Race X and Xenian aliens use organic weapons in combat (Race X Shock Troopers using Shock Roaches and Spore Launchers while the Xenian Grunts use the Hivehand) and teleportation technology.Newspaper reporting the purchase of the salt mineĪperture Science was founded as Aperture Fixtures in the early 1940s by Cave Johnson. Despite their physical differences, Race X and Xen aliens do have some things in common. Some of the Race X creatures are used by the Gene Worm is also present in Black Mesa.

It is likely that the rift to their dimension was sealed off by Black Mesa's destruction, removing their only access point to Earth and preventing them from spreading across the planet. Their eventual goal were stopped due to Adrian Shephard. The smaller Race X troops begin to make way for the Gene Worm. They might also have used the Gene Wormportal, which may have been the original portal to the Race X homeworld in Black Mesa. The Resonance Cascade probably affected portals linked to their world, allowing them to teleport into the Black Mesa facility in great numbers Some apparently teleported into Xen as well. The aliens of Race X have no relation to those of Xen, and did not cooperate with them. The designation 'X' was used by Black Mesa to refer to the dimension and its inhabitants. Race X was discovered by chance by Black Mesa scientists when they opened a rift to another dimension than that of Xen during their portal technology experiments, which lay 'Somewhere beyond Xen'. They were not particularly well adapted to the Borderworld, and never had a notable presence on Xen. They used the Xen teleporter during to bring Sprites prior to the invasion. Race X appears teleport around Black Mesa and have one Xen crystal-powered teleportation device on Xen. They invade the Black Mesa Research Facility late in the Black Mesa Incident. Race X is the designation given to an alien race which serve as the main antagonists of Half-Life: Opposing Force.

Black mesa research facility vs portal