The BioDerm Hordes are genetically engineered lifeforms originally created by mankind as laborers and HERC pilots. They rebelled against their human creators and took control of their own genetic codes, breeding themselves into better warriors. The BioDerms were a playable "tribe" and the primary antagonists in Tribes 2. In Tribes: Ascend you can purchase 3 Voice Packs that replaces the default VGS voice with a BioDerm's voice, also the Raider class' Griever skin has a BioDerm skull on it's shoulder pad and the description of the TNC4 Rockwind SMG says it can drop a BioDerm.
As genetically engineered lifeforms, BioDerms served for centuries as warriors for the Empire and its corporations. Originally created to fight the Cybrids, they continued to see combat in various internal conflicts. In 3734, the mighty Gir Draxon led the rebellion that freed the BioDerms and set them on a crusade to claim Earth for their own. While the battle with the Empire has raged long, they have just now turned their attention to tribal space, launching a massive invasion force into the Wilderzone.The BioDerm remain under a shroud of mystery, their beliefs and rituals hidden from outside eyes. Their fanged grins and cold eyes seem designed to chill the blood, and their visage ever haunts the few who have seen them up close and lived to tell of it. While they consider themselves superior to humans, they often feel they have something to prove. This, in addition to a deeply-held grudge for their enslavement, drives them forward in a relentless assault on human space.
It take only days to generate a BioDerm in special chambers called "biowells". Upon emerging from the well, they undergo a rigorous regimen of chemical and physical conditioning, virtual reality training, and combat psycho-programming. In less than a few weeks, these 'instant' warriors are more than a match for the finest of human fighters. In battle, the 'Reavers' unleash that fury that is part of the essence of all BioDerms. They are bred for war and live to conquer.
The BioDerm invasion is composed of three mighty Hordes, each consisting of multiple "Bloodstrains". The Strains are well equipped for independent operation, yet they display an uncanny ability to coordinate efforts with little or no preparation. Each Horde has its own style and methodology of warfare, and their foes will find both brute force and subtle cunning used against them. Combined with their extensive intelligence gathering and raw physical power, the Derms appear unstoppable as they stand on the brink of ultimate conquest.