Unity

The Unity is the Master's insane vision of the future evolution of the human species. By dipping everyone in FEV and turning them into super mutants, the master believes that he can 'unify' all people by making them equal annd highly adaptable to the wasteland humanity made for itself. In Fallout 1, it is the Vault Dweller's job to make sure this vision is crushed, burned and buried in an unopenable vault.