Hell Is Us: Complete Guide to Vaults of Forbidden Knowledge Locations and Codes

The Vaults of Forbidden Knowledge in Hell Is Us are concealed passages that offer players exceptional rewards such as defensive gear, unique weapons, and intriguing lore items. These vaults are not only difficult to locate but also require a specific code to unlock.

To reveal the codes necessary for accessing these vaults, players must gather research items and submit them to Tania Alver at the APC. By accumulating sufficient items, you will receive hints about the vault’s location and the corresponding unlock code.

This comprehensive guide will outline each Vault of Forbidden Knowledge’s locations, codes, and the rewards they offer.

Comprehensive List of Vault Locations, Codes, and Rewards

In total, six Vaults of Forbidden Knowledge can be found within the world of Hell Is Us. Each primary area features one vault, with the exception of Talju.

Senedra Forest Vault: Location & Code

The Senedra Forest Vault can be discovered adjacent to the camp where you first find the Medkit for the injured soldier early in the game. If you’re unsure of its location, look for the white X’s on the trees leading uphill from the APC parking spot.

Upon reaching the camp, navigate through the tent and turn sharply right to spot a small crevice in the mountainside. Proceed through this opening to uncover the Vault of Forbidden Knowledge.

The code to unlock the Senedra Forest Vault is: Terror, Admiration, Rage, Amazement.

Rewards from the Senedra Forest Vault

Once the Senedra Forest Vault is opened, players can collect the following rewards:

Acasa Marshes Vault: Location & Code

The Acasa Marshes Vault is situated within the locked base camp near Jova. You will acquire the base camp code during the story, but it is available for input at any time. The code for the gate is 151991.

Once through the gate, navigate through the camp and circle around to access a large cave that descends underground. Keep progressing to find the Vault of Forbidden Knowledge.

The unlock code for the Acasa Marshes Vault is: Rage, Ecstasy, Terror, Grief.

Rewards from the Acasa Marshes Vault

The Acasa Marshes Vault is rich in rewards. Below is the list of items you can obtain:

Vyssa Hills Vault: Location & Code

Vyssa Hills Vault, head behind the waterfall near the map’s edge. Ascend the hill leading to the waterfall’s apex, then drop onto the rocky platform below. Proceed through the waterfall and follow the path downward to unveil the Vault of Forbidden Knowledge.

The code for unlocking the Vyssa Hills Vault is: Admiration, Amazement, Ecstasy, Rage.

Rewards from the Vyssa Hills Vault

Upon accessing the Vyssa Hills Vault, players can expect the following valuable rewards:

Rewards	Type	Description
Glyph – Rapture – Enhanced	Glyph	Surge of energy around you damages all nearby Lymbic Entities.
Letter – A Spy’s Insight	Miscellaneous	In-game lore item.
Pendant of Ecstasy – Battle Bliss	Defensive Gear	This item weakens strike-based damage while grievously wounded.
Parchment – Anticipation	Miscellaneous	In-game lore item.
Glyph – Animosity – Enhanced	Glyph	A hatred lasso captures a targeted Lymbic Entity, pulling them back into melee range.
The Unbound Delusion	Passive Relic	This item increases Lymbic Energy but reduces damage taken.
Glyph – Void – Enhanced	Glyph	A melancholic pool erodes entities within and can be collapsed for increased torment.
Painting – Lady Marguerith	Miscellaneous	In-game lore item.

Lake Cynon Vault: Location & Code

The Lake Cynon Vault is positioned on the eastern side of the map. Upon entering the area filled with blue flowers, take a right and continue toward the water to discover an opening in the mountainside. Navigate through the tunnel to locate the vault.

The required code for the Lake Cynon Vault of Forbidden Knowledge is: Vigilance, Grief, Loathing, Ecstasy.

Rewards from the Lake Cynon Vault

Upon unlocking the Lake Cynon Vault, players will receive the following rewards:

Reward	Type	Description
Glyph – Perfect Guard – Elite	Glyph	This glyph reduces stamina loss when blocking an attack.
Tuning Stone – Steady	Usable Item	This grants your weapon +1, 500 experience points.
Glyph – Lymbic Silvers – Elite	Glyph	This creates multiple shards of ambient Lymbic energy directed at your target.
Tome – The Ascendance of Hellion Lodges and the Birth of Lymbic Aesthetics, Part 1	Miscellaneous	In-game lore item.
Memoria of the Phol	Active Relic	Your weapons gain experience faster due to resonance with past battles.
Amine Prism – Theta	Exploration Item	This can be utilized to close certain Timeloops.
Painting – Scion Namir Adam	Miscellaneous	In-game lore item.
Parchment – A Dire Cost	Miscellaneous	In-game lore item.

Marastan Vault: Location & Code

The Marastan Vault is accessible by turning the first left from the main road where the APC is stationed. This vault is situated in the southeast area of the map, beyond the large ruins populated by enemies.

After navigating past the ruins, proceed to a small island featuring a rock formation. Enter the opening behind this structure to reach the Vault of Forbidden Knowledge.

The code for the Marastan Vault is: Amazement, Vigilance, Admiration, Loathing.

Rewards from the Marastan Vault

Throughout the Marastan Vault, players will find an array of significant rewards listed below:

Reward	Type	Description
Glyph – Frightful Ambush – Elite	Glyph	Creates a pool of terror energy that causes pain to captured Lymbic Entities.
Painting – Queen Raveta	Miscellaneous	In-game lore item.
Glyph – Masochistic Delight – Elite	Glyph	You voluntarily inflict damage upon yourself and share the ecstasy with nearby Lymbic Entities.
Glyph – Waves of Grief – Elite	Glyph	Endless grief energy spills from your weapon, tormenting Lymbic Entities.
Orison of Valour	Active Relic	Removes all Stamina costs during combat.
Amine Prism – RHO	Exploration Item	This can be utilized to close certain Timeloops.
Glyph – Rage Spike – Elite	Glyph	A lance of rage bursts forth from your weapon and detonates upon contact with a target.
Parchment – Regret	Miscellaneous	In-game lore item.
Tome – The Ascendance of Hellion Lodges and the Birth of Lymbic Aesthetics, Part 3	Miscellaneous	In-game lore item.

Jeljin Vault: Location & Code

Jeljin area, you can find the Vault of Forbidden Knowledge by going southwest from the APC, where a small camp with tents is located. Inside one of the tents, a staircase leads underground to the vault.

The access code for the Vault of Forbidden Knowledge is: Grief, Loathing, Vigilance, Terror.

Rewards from the Jeljin Vault

Last but not least, the Jeljin Vault rewards players with valuable items detailed below:

Reward	Type	Description
Chalice of Everflowing Turmoil	Active Relic	Siphon Lymbic Energy from enemies to replenish your own.
Polearm of Grief	Weapon	Guard Protection: 10%, Lymbic Theft: 16%, Parry Agility: C, Attack Speed: B.
Sword of Rage	Weapon	Guard Protection: 15%, Lymbic Theft: 13%, Parry Agility: B, Attack Speed: C.
Parchment – Vanished	Miscellaneous	In-game lore item.
Twin Axes of Terror	Weapon	Guard Protection: 0%, Lymbic Theft: 12%, Parry Agility: A, Attack Speed: A.
Greatsword of Ecstasy	Weapon	Guard Protection: 20%, Lymbic Theft: 15%, Parry Agility: D, Attack Speed: D.
Tome – The Silent Safeguard	Miscellaneous	In-game lore item.
Tome – The Ascendance of Hellion Lodges and the Birth of Lymbic Aesthetics, Part 2	Miscellaneous	In-game lore item.

Source & Images

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