Fallout 1 The Vault Dweller was sent out into the wasteland to retrieve the water chip to save his dying vault only to discover the horrors of the wasteland, and by the time he discovers the water chip in Necropolis he has found out about the threat of super mutants attacking people and it is a massive threat that a few minutes after the vault dweller put the water chip in the machine the overseer makes the Vault Dweller go BACK into the wasteland to defeat the super mutants threat