10 Terrifying Fallout Vaults You Wish You'd Never Opened

10. Vault 51 - Fallout 76

A true leader is an individual who steps up in the face of crisis.

It was this one simple and fairly throwaway line that ended up being the entire downfall of Vault 51, as whilst other vaults were run by Overseers made of flesh and blood, this Vault was run by a computer known as ZAX.

ZAX's directive was to find the "perfect Overseer" from the residents of the Vault, which sounds simple enough, but after repeated failures with voters only voting for themselves, class disputes and all forms of trials in between failed to produce a sole winner, ZAX took matters into its own hands.

Thanks to a comment made by an advisor to the robot, ZAX began instigating challenges and trials for the residents to overcome as a means of finding someone who would step up and take control. Water supplies were turned off, food withheld and sleeping arrangements shifted, all of which resulted in infighting and distrust.

Things came to a head when ZAX revealed that the only true way to have a clear winner was for the residents to kill one another until only one remained. Oh, and to make matters worse ZAX wasn't happy with the winner and locked him out of areas of the vault causing the man to sink into a depression. Brilliant.