Xenos - Abhuman Species: In the long millennia since Mankind first began to settle amongst the stars, some Human colonists have deviated to a great degree from the base-line Human genome due to exposure to the alien environments of their homeworlds and long centuries of isolation from the rest of Humanity during the Age of Strife. These sub-species of Humanity often differ in physical and cultural terms from the Human baseline to such an extent that they are almost as inhuman as true xenos. These variant Human sub-species are generally referred to by the Administratum as Abhumans.Interex - The Interex was a highly advanced interstellar Human civilisation that existed across some thirty star systems at the time of the Great Crusade in the early 31st Millennium. The Interex, unlike the Imperium of Man, had decided that the best way to deal with intelligent alien species was not to exterminate them or make war upon them, but to try and coexist with them. In fact, the Interex had become the close allies and nominal overlords of a simian alien species called the Kinebrach who they had integrated into their own society. The Interex ultimately became enemies of the Imperium after hostilities between the two Human civilisations began when the Interex accused a diplomatic party of Luna Wolves led by the Warmaster Horus of breaking into their Hall of Devices, a museum on the Interex world of Xenobia dedicated to weaponry, and stealing a prized Kinebrach blade called an Anathame that was known to have links to Chaos. The Interex believed that the Imperium was allied to Chaos (which they called "Kaos") and never knew that the weapon had in fact been stolen by First Chaplain Erebus of the Word Bearers Legion, who had been with Horus' diplomatic party. Unknown to Horus, Erebus and the Word Bearers Legion had already turned to the worship of the Ruinous Powers of Chaos. The powers of the Warp had informed Erebus and his Primarch Lorgar that if they wished to bring Horus over to the side of Chaos, then they would need the Kinebrach Anathame. The Interex civilisation was ultimately wiped out by the Luna Wolves, following the commencement of hostilities between the two Human factions on the night Erebus stole the Anathame.Ogryn (Homo sapiens gigantus) are a huge and physically powerful Abhuman mutant subspecies of Humans, often employed as shock troopers in the Imperial Guard by the Imperium of Man. Ogryns possess many traits prized by the Imperium; they are brutally strong and completely loyal, although extremely limited intellectually, which limits their battlefield role to simple and direct assaults. They come from cold and barren planets in the galaxy with high gravity, such as Anark Zeta, which is why they appear larger, heavier and bulkier compared to baseline Humans. An Ogryn's speech is much the same as an Ork's. The most famous Ogryn in Imperial service is Nork Deddog.Olamic Quietude - The Olamic Quietude was a technologically advanced cybernetic Human civilisation that had been founded during the Dark Age of Technology and over the course of 15,000 standard years merged themselves so completely with their advanced technology -- as a possible result of the influence of unknown xenos -- that there was little left of them that could be considered truly Human. The Quietude lived in vast and deep techno-hive cities protected by an artificially-extended icecap on their unnamed homeworld, an otherwise lifeless but heavily defended planet. They were encountered by the Imperium of Man's 40th Expeditionary Fleet near the end of the Great Crusade in the late 30th Millennium, and utterly annihilated by the 3rd Great Company of the Space Wolves Space Marine Legion, another of the Abhuman pretenders to the Human future wiped out by the forces of the Emperor of Mankind.Ratlings (Homo sapiens minimus) are small, loud, hungry and lecherous Abhumans. Ratlings are granted full Imperial citizenship despite their mutant status and in the past have often served in the Regiments of the Imperial Guard. However, they are still distrusted by the more Puritanical members of the Inquisition.Squats (Homo sapiens rotundus) - The Squats are a short, stocky and physically hardy Abhuman sub-species of Mankind who were adapted to the heavy gravity conditions that predominated on the worlds they had settled near the core of the Milky Way Galaxy. Of all the Abhuman types encountered by the Imperium, they most closely resembled baseline Humans. Squats were the descendants of baseline Humans who had colonised the worlds around the galactic core in the far distant past of the Dark Age of Technology. These worlds are some of the oldest in the galaxy, formed when the galaxy's structure had not yet been fully stabilised. The Squat species was ultimately destroyed by the invasion of a Tyranid splinter Hive Fleet that consumed their homeworlds in the late 41st Millennium, though some survivors still see service with the Imperial Guard, hoping for revenge and to find a new beginning for the remnants of their race.