The Arachnids (more commonly known as Bugs, and Archies) are an alien race that has evolved and conquered several planets outside any territorial space. The Arachnids were originally believed to be mindless creatures. When Johnny Rico and Carmen Ibanez dissect Arkellian sand beetles, the Allied biology teacher states that the Arachnids have millions of years of evolution behind them and are, in the case of survival capability, the perfect species. They have the ability to colonize planets "by hurling their spore into space" and possess a social structure which fits their mental capabilities. As the Arachnid War progressed, it became clear that they have a caste system, with each subspecies filling a specific role. Brain Bugs and God Bug have extreme psychic abilities that can be used to control all bugs in the colony. Most types of the Bugs are less intelligent, except for the Brain Bug, Control Bug, God Bug, and the Queen. The Bugs are probably the most extremely hostile to every sentient races.