Vault-Tec might have helped ‘millions’ of people find shelter amid a nuclear war that completely changed how people view survival in the Fallout franchise. But beneath the surface, the mega-corporation was just as guilty of exploiting its customers as pretty much any other.
Many of these vaults were considered Control Vaults, which worked exactly as Vault-Tec had advertised: safe, underground bunkers filled with food and supplies to survive until the vault opens and people are able to repopulate the surface.
Unfortunately, another chunk of the vaults was used for social and medical experiments, with many of their inhabitants fading away slowly or suffering cruel and horrific deaths. Of all of these, there are a handful that I personally believe to be the most heinous and malicious Vault-Tec experiments in Fallout, ranked.
7
Vault 95
Fallout 4 | Drug Addicts Made Clean Then Informed of Secret Stash

Trying to live a sober life after addiction can be a rollercoaster, and I’m sure it’s no different in the Wasteland. I’m sure it’s actually even more difficult to get the help you need in a place where everyone is irradiated or injured in some way.
That’s what makes Vault 95 so jarring. It was an experimental vault in which residents suffering from different addictions could go to attend the Vault-Tec Rehabilitation Program and basically prove that, with no other alternative, a person can recover from addiction. After residents were cured of their illness, a Vault-Tec agent disguised as a Vault Dwellers was tasked with planting and opening a stash of drugs.
After this revelation, the now-rehabilitated Vault Dwellers fought and killed one another, completely destroying any bonds they had. If you enter the vault, you can find a recording of a resident who discovered the plan, voicing their anger at Vault-Tec.
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Vault 112
Fallout 3 | Living in a Simulated World

Living in the Wasteland is already incredibly tough, but not knowing that it’s out there to begin with is a strange kind of cruel. Canonically, it was among the very last vaults to be created and was initially intended to allow the creator of the G.E.C.K. to create a world suspended in a virtual reality.
Despite this virtual world being called Tranquility Lane, it was anything but tranquil. Almost immediately after entering the vault, the residents were placed in the simulation and forced to stay there, being playthings for the Overseer. What’s even worse is that the Overseer had the ability to kill and resurrect them within the program. I can only imagine what that does to the psyche.
I personally put it on this list because, within Fallout 3, Vault 101 and Vault 112 are pretty much the only ones intact, meaning that the residents could have also lived safe and healthy lives if not for the Overseer’s god complex.
5
Vault 22
Fallout: New Vegas | Transforming Into Spore Carriers

Vault 22 wasn’t created initially as an experiment at all, which is partly what makes its demise so devastating. Instead of residents, the vault was occupied by scientists looking to revolutionize crop production to aid in agricultural initiatives after the Great War.
Unfortunately, things went a little sideways when their research led them to the Beauveria mordicana, a fungus that was meant to keep pests away from plants. The fungus was originally meant to be a kind of parasite, taking over the bodies of pests so they can infect others. But instead, the scientists discovered that the fungus affects humans in the same way.
Before long, the vault was emptied of living residents, with everyone else having become a weird, green spore carrier. Not even the game canon gives a clear picture of what happened to those Vault Dwellers after the vault fell into disrepair.
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Vault 106
Fallout 3 | Slowly Drugging Residents

The residents of Vault 106 were unfortunate to be chosen for one of Vault-Tec’s strange experiments. This time, the mega corporation wanted to know what would happen if they let out psychoactive drugs into the air via the vault’s filtration system. Every time someone complained about the air being a little funky, they were all but dismissed.
Now, over 200 years since the bombs originally dropped, the place has pretty much become a bubble of hallucinogens. People who enter are immediately drugged and experience hallucinations all throughout. As the player character, you’ll even start seeing hallucinations of your father and other people you know while down there.
What I found to be the most devastating is when you reach the end of the vault. It appears as though the Vault Dwellers had tried to escape by digging out of the vault and through the ground, but were just unsuccessful in their attempts.
3
Vault 92
Fallout 3 | Using White Noise to Slowly Make Residents Insane

The residents of Vault 92 were all renowned musicians from all over the country. The whole point of putting them all in one place was supposedly to preserve musical talent, but that was quickly disregarded after the doors shut. Instead, Vault-Tec asked the first overseer of the vault to experiment with the effects of white noise, implanting violent thoughts into the residents.
After a while, some of the residents started being a little too violent, and different fatalities were reported often. That wasn’t even the worst of their problems, seeing as the vault was deteriorating due to having been built close to underground water sources that began seeping in.
With the vault flooded and most of its inhabitants dead, the place became abandoned, and the project stopped. It’s no wonder Galaxy News Radio plays the same songs over and over again.
2
Vault 75
Fallout 4 | Using Eugenics To Create Perfect Soldiers

What happened in Vault 75 is actually pretty insane. Vault-Tec had originally advertised it as a safe haven for children who attended the school it was built below. However, after the vault closed, children were separated from their parents, and the adults were all executed.
The children succumbed to a variety of brainwashing techniques that made them believe that all their suffering would eventually help the suffering people in the wasteland above. Unfortunately, the real truth was that when the kids turned 18, their exceptional genes were harvested for an unknown reason.
If you weren’t among the lucky kids who had good genes, then you were killed and incinerated right after graduation. It’s no wonder it ended up being a graduate who caused a rebellion within.
1
Vault 77
Fallout 3 | A Single Man and His Puppets

Vault 77 isn’t actually in the game, but it was used in a comic to promote Fallout 3 prior to its release, and I personally think it encapsulates both how terrifying and sort of silly Vault-Tec can be. I’m unsure of exactly how it happened, but the vault was sealed with only a single person inside and a crate of hand puppets.
Not long after discovering the puppets, he descended into a madness that made him believe the puppets were actually talking to him. This quickly led to additional mental anguish that caused the Puppet Man to murder a different puppet and escape the vault for fear of what the other puppets might do.
The Puppet Man’s jumpsuit somehow made its way to Paradise Falls, where even the people selling it want absolutely nothing to do with it, but refuse to do anything to it out of superstition.

