The Mutant social structure has settled into four distinct groups, called Tribes, who utilise unique skills and talents of the individuals for the good of the whole of the Mutant people (The Tribes of the Changed). The names of the tribes come from their relationships to the Contamination in a spiritual or physical matter. The Spirit Tribe is made up of Archons who first perceived the influence of the Contamination; the Earth Tribe are master crafters using both technology and the environment; the Bear Tribe stems from the aggressive fighters or Champions of the Mutants; and the Insect Tribe is composed of the Avengers, who hold a deep reverence for the land and act as spies and intelligence gathers. Each Tribe provides a leader to a council that governs The Tribes of the Changed, though the chief member of the council is always the Prime Archon.