Insane survivor

Insane survivors are the hostile inhabitants of Vault 106

Background
As part of the Vault experiment, experimental psychoactive drugs were released into the air filtration system of Vault 106 ten days after the door was sealed. The drugs affected some, but not all residents. This is evidenced by the note To anyone who gets this, which was written by someone who was not affected or was to a lesser degree. It seems as though the drugs sparked violence in those they affected, resulting in the "insane" killing everybody else in the Vault, leaving only a few survivors.

Appearances
Insane survivors appear only in Fallout 3.