Summary
The world ofFalloutcontains many different stories within the wasteland. Some of the safest havens inpost-apocalyptic Americaare the vaults established by Vault-Tech. These vaults were meant to survive an atomic blast and keep the vault dwellers safe against any outside threats. They also housed plenty of resources to keep humanity afloat.
Unfortunately, the vaults are not all what they seem. Instead, Vault-Tech also elected to run a variety of different experiments at each location. Some were designed to drive their inhabitants towards violence over time, while others forced them to make questionable choices for their own survival. These are the most terrifying vault experiments.

10Vault 4
Human Experimentation
So the bombs have dropped and you find yourself deep inside a vault. Unfortunately, the vault is run by scientists who now have unrestricted authority to experiment on humans as they see fit. This is what happened in Vault 4during the Fallout TV Series.
The scientist in charge would conduct mutation experiments by splicing human DNA with the DNA of radiation-resistant creatures. This resulted in the creation of gulpers. They would even lure in other survivors from the wasteland to use as additional test subjects.

9Vault 11
A Yearly Sacrifice
Deep in the Mojave Wasteland inFallout: New Vegas, a terrifying social experiment was underway. Vault dwellers in Vault 11 would be faced with an impossible task. Each year, they were to vote for one person among them to die. Doing this would keep the entire population alive. Failure to vote would kill everyone.
This yearly sacrifice continued until only five vault dwellers remained. What they didn’t know was if, at any point, the inhabitants refused to participate, the vault doors would be opened and the dwellers, be congratulated for their perseverance.

8Vault 19
Red Vs Blue
Vault 19 divided its inhabitants by faction. Some would be assigned to the blue side, while others would be assigned to red. Both sections of the vault would be divided with limited contact between them. They even had two separate overseers.
During the experiment, vault dwellers would be subjected to artificially induced paranoia. This would cause them to hear strange noises and experience mechanical malfunctions within the vault. Soon, both sides would blame the other for their misfortunes when the true troublemakers were the overseers.

7Vaults 31, 32, And 33
Bud’s Buds
Consisting of three vaults connected to each other, Vault 31, 32, and 33 existed to create the most loyal vault tech employees. The three vaults would be used as support systems in case any one of them found themselves raided or attacked.
The experiment consisted of breeding the ultimate Vault-Tech employee using loyal Vault-Tech crews from one vault and intermarrying them with the genetically superior residents of the other vault. The end result was for the new population to rise to the surface and monopolize the wasteland once everyone else was dead.

6Vault 87
Super Mutant Experiment
Super mutants and centaurs aresome of the most horrific and dangerous creaturesin the Capital Wasteland. In this region, they all came from Vault 87. Originally, scientists would conduct research that mutated other humans into super mutants using a forced evolutionary virus.
Eventually, the super mutants would revolt against their creators and take over the operation. Now kidnapping humans from the surface, the super mutant population would multiply and spread across the wasteland in search of more FEV to use on unsuspecting humans.

5Vault 92
Musicians Vs White Noise
If you happen to be one of the world’s greatest musicians, then you have just earned your ticket to safety. Vault 92 was specifically made to preserve your talent for future generations. This, of course, was a lie, with the true intentions of the vault being white noise and sound experiments.
This low-frequency noise was emitted to the unsuspecting musicians with the intention of perfecting a form of mind control and implanting suggestions. This would eventually backfire as the musicians succumbed to the violent side effects and overtook the vault.

4Vault 106
Chemicals In The Air
Located in the Capital Wasteland, Vault 106 conducted a drug experiment on its residents. The experiment would pump drugs through the ventilation system, which would slowly cause paranoia and increase violent tendencies.
While the overseer was aware of the true nature of the experiment, that knowledge did not stop the vault from falling. Eventually, the survivors in the vault would overrun their overseer in a revolt. However, the vault continues to pump the chemicals long after these events, affecting anyone that gets close.

3Vault 108
A Bunch Of Weapons And A Cloning Machine
Vault 108 was located in the Capital Wasteland. While many vaults were filled with supplies to keep the population alive, Vault 108 came with pre-planned system failures. Despite claiming to have accommodations to last 38 years, power was set to fail in only 20.
In addition to this, standard entertainment was non-existent while weapons were made heavily abundant. Eventually, the scientists began cloning experiments, leading to a man named Gary being cloned repeatedly. Unfortunately, every clone that was produced came with violent tendencies that eventually led the vault to ruin.

2Vault 111
Cryogenic Stasis
Vault 111, was located in the Commonwealth. As one of the vaults in Massachusetts, the bombs could be seen dropping at the start ofFallout 4as residents struggled to be let in. Once inside, the new vault dwellers were instructed to put on a vault suit and enter a pod.
Unbeknownst to them, this was part of an experiment to see the long-term effects of cryogenic stasis. The playable character would wake up hundreds of years after the bombs dropped. As for the staff, they fought to the death after new orders failed to come in.

1Vault 77
Beware The Puppet Man
Loneliness can make anyone seek companionship. One vault in particular was featured in aFallout 3webcomic that depicted what happens when only one person is left inside a vault. The experiment in Vault 77 placed a single human inside the vault surrounded by crates.
These crates contained a variety of different puppets as the sole source of companionship. The lone survivor would come to be known as The Puppet Man, role-playing each of his puppet’s personalities to keep himself occupied. He would continue to do this long after escaping the vault.