With the Vault-Tec Workshop expansion in Fallout 4, players were granted access to a new potential settlement in the game called Vault 88. Tucked below the Quincy Quarries this massive vault holds a dark and tragic past that players can uncover as they clear out enemies and knock down walls to expand the vault and build a thriving base.

For those who haven’t gotten around to exploring this haunted area there are number of secrets and strange things that can be found in this important location.

10 Overseer Barstow Is The Only Sane Survivor

After entering Vault 88 players come across Overseer Barstow, she’s a feral ghoul who has managed to hang onto her sanity through sheer willpower and extreme devotion to her role in Vault-Tec’s twisted experiments.

Her other companions haven’t fared so well as the radiation poisoning and transformation into feral ghouls has driven them insane beyond the point of return. No one would consider Overseer Barstow sane considering her opinions on the hypocritic oath, but the fact that she retains free will and cognitive thought as a feral ghoul is very impressive.

9 Shady Purpose

Vault 88 was built by the Vault-Tec corporation to be a massive test lab for a number of experimental technology to be used in other vaults. Things like the Phoropter that can bombard a subjects mind with subliminal messages that can either increase their level of happiness or kill them.

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Overseer Barstow retains the blueprints to many of these machines that would be used on the inhabitants and is devoted to carrying out those experiments even though Vault-Tec is no more. It’s eerie to think what would have happened to vault dwellers here had the place been finished prior to the apocalypse.

8 The Other Survivors Aren’t Vault Dwellers

Vault 88 was under construction during the time of the attack. They had managed to finish the entrance and main lobby, but not much else. When the bombs fell the construction crew, security forces, and invited VIPs brought to tour the Vault were the ones present and fled into the vault to survive.

With the vault being unfinished everyone was flooded with radiation and gradually become feral ghouls with only Overseer Barstow retaining her sanity. It’s disturbing to think these poor souls probably considered themselves lucky to make it into the vault during the nuclear attacks only to become mindless monsters later.

7 Legendary Deathclaw

With the broken tunnels and loose rubble a number of creatures found their way into the unfinished parts of the Vault and took up residence. One of these creatures is a Legendary Deathclaw found in the northern section of the Vault.

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It’s possible that the Deathclaw was a captive creature of Vault 88 for the experiments, but there’s nothing in the northern section of Vault 88 like cages to suggest this is the case. More than likely it wandered in and made a home for itself.

6 Mirelurk Queen

Another creature to find a home in Vault 88 is the Mirelurk Queen and her brood of leveled Mirelurks. The nest of Mirelurks can be found after gaining access to the East Sector, in this sector is a large cavern jam-packed with Mirelurks and their Queen.

Considering Mirelurks are the result of mutation from radiation these were not here when Vault 88 was built and their presence is coincidental. The Mirelurk Queen is very dangerous, especially with her underlings assisting her in combat so tread carefully when entering the East Sector.

5 Lots Of Uranium

Once the areas are relatively clear you need to jump into workshop mode to start clearing out the space to put your expansions in. If you carefully explore each area for scrap you’ll find that not only is there a vast amount of concrete and steel to be found, but rare and valuable nuclear material from uranium deposits.

Nuclear material is used to create powerful weaponry like Cryogenic Grenades and is used in the ammo found in the Nuka-World expansion. Carefully clearing out these uranium veins will net 100+ nuclear material to craft to your heart’s content.

4 University Point Pharmacy Entrance

If you tried finding the entrance to Vault 88 without a guide, you’ll know that it’s somewhat out of the way and kind of obnoxious to use as your own method of entering and exiting the base. Fortunately, if you proceed to clear out all the areas and expand Vault 88 you get access to a new entrance.

It turns out that Vault 88 lies directly beneath the University Point Pharmacy and a secret entrance is created, leading into the Vault.

3 Prototypes

As part of fulfilling the quests for Overseer Barstow you are tasked with performing experiments on subjects to test out prototype technologies. These prototypes can have negative and positive effects with some capable of outright killing the test subject. After finishing these quests you can construct these prototypes to be used in any of your settlements.

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The Phoropter will improve a settler’s happiness, the Slot Machine can raise happiness levels or generate income for the player, the Power Cycle 1000 can be used to produce power, and Soda Fountains can raise happiness and decrease hunger. Sure, they might have been invented out of a disregard for human's rights, but putting them to ethical use for your settlers can make life in the wastes better for everyone and make settlement management a whole lot easier.

2 Vault 88 Is Massive

While building Vault 88 you’ll come to realize that it’s massive. In fact all those sectors put together adds up to a space that’s five times the size of Sanctuary Hills, it even rivals the biggest settlement in the game Spectacle Island.

What’s even better about Vault 88 is that enemies will only use the main door to invade, meaning you can concentrate all your defenses to create a kill zone outside your main door. That leaves the entire interior open to build whatever you want. It’s strongly recommended you get a mod that removes the building cap so you can grow crazy in this massive space.

1 Legend Of Vault 88

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In addition to getting one of, if not the, largest settlement in the game you also are granted a special uniform for completing Overseer Barstow’s missions. As thanks for your help, and assuming you haven’t killed her, she provides you with the Legend Of Vault 88. It’s a Vault 88 jumpsuit that has energy and radiation resistances, as well as damage reduction from ghoul attacks.

In reality if you’ve progressed this far, killed the legendary Deathclaw and the Mirelurk Queen you probably wont need this. It is a nice unique outfit that functions as an in-game trophy for all your hard work unlocking the secrets and potential of Vault 88.

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