Check out this DOOM Eternal guide about the Fortress of Doom! Learn recommended unlocks, secrets & collectibles, facilities, skins (suits), computer password, cheat codes, & more!
About the Fortress of Doom
Secrets & Collectibles
Fortress of Doom Facilties
Recommended Unlocks
Prioritize The Sentinel Crystals

There are 2 Sentinel Crystals that can be found in the Fortress of Doom. Invest your first Sentinel Batteries on unlocking these Sentinel Crystals as they provide a permanent boost to your health, armor, and ammo. They also reward you with a passive combat bonus!
Check Out The Sentinel Crystal Guide Here!Get Weapon Mods Next

The Modbots located here can give additional options when fighting against the demonic horde. Use your spare Sentinel Batteries to open these rooms after you have unlocked the 2 Sentinel Crystals.
Check Out The Weapon Mod Guide Here!What is the Fortress of the Doom?
The Doom Slayer's Hub

The Fortress of Doom is the Doom Slayer's main hub. Here the player can relax, and check out their overall progression with the game by interacting with different items and facilities located within.
Powered By Sentinel Batteries

The Fortress of Doom is powered using Sentinel Batteries, which are found throughout different levels and worlds that you explore while playing the story! Using these batteries in the fortress will unlock new facilities, and even new skins for the Slayer!
Check Out The Sentinel Battery Guide Here!Secrets & Collectibles Overview & Map
Fortress Of Doom Collectibles
Collectible | Quantity |
---|---|
Skins | 3 |
Modbots | 2 |
Sentinel Crystals | 2 |
Praetor Suit Points | 4 |
Codex | 1 |
Cheat Codes | 2 |
Weapon | 1 |
Fortress Of Doom Collectibles Map

Requires 22 Batteries To Unlock
You need to have 22 Sentinel Batteries to unlock everything in the Fortress of Doom. You can collect Sentinel Batteries in missions and you can replay them to get those that you missed.
Check Out The Sentinel Battery Guide Here!Unlock Suit & Weapon Upgrades

The Fortress of Doom will also have several upgrades just waiting for you to unlock! Unlock 2 Sentinel Crystals, 2 Modbots, and 4 Praetor Suit Points! Each upgrade will need 2 Sentinel Batteries to unlock. It is recommended to get the Sentinel Crystals first as they will benefit you most in the long run!
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Check Out the Upgrades List Here!Unlock Skins For the Slayer

You will find different skins for the Slayer while exploring the fortress. The skins are locked behind doors which require 2 Sentinel Batteries to open. Once unlocked, you will then be able to change the appearance of the Doom Slayer!
Skins In The Fortress Of Doom
![]() Click to Enlarge Sentinel | ![]() Click to Enlarge Praetor |
![]() Click to Enlarge Classic | - |
Cheat Codes
All Runes Cheat Code

You need to unlock the Praetor Suit for this Cheat Code. At the left side of the Praetor Suit's room is a hole that you can drop down from to reach the cheat code. You may want to equip the Chrono Strike rune to slow down time while you drop, giving you more control.
Fully Upgraded Suit Cheat Code

You can get this Cheat Code at the before you jump to Mission 10. In the room where the Crucible is placed, fire at the red panel located at the upper right window. This will open a jump pad that will take you up to the vents. Drop down to get the Cheat Code.
Check Out All Cheat Codes Here!Unlock the Unmaykr

Players will be able to unlock the Unmaykr weapon in the Fortress of Doom! It is barred behind a six-lock contraption, which is unlocked by using Empyrean Keys you find hidden throughout the game!
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Facilties In the Fortress of Doom
Ripatorium / Demon Prison

The Ripatorium or the Demon Prison will allow you to hone your skills in combat as the slayer! Activating the Ripatorium will release a wave of demons which you can kill to get better at the game!
Kill Demons With No Consequences
Losing or dying in the Ripatorium will not deal out any consequences to you since it serves as a training area. You will not receive any penalty from losing in the Demon Prison!
Check Out All Enemies Here!Warp Gate

This facility will allow you to select different missions from the campaign. This will allow you to replay levels, helping you explore the map, find collectibles, and more!
Take on Master Levels

The Warp Gate will also allow you to take on Master Levels! These are variants of the levels you play in the main game. These variants will have different enemy placements, and even new enemies spawning in certain locations. Be ready for a challenge!
The Slayer's Room

You can find the Slayer here when he isn't out and about killing demons left and right. In the Slayer's room, you can find out what he likes to do in his spare time! There are several things you can check out in the Slayer's Room!
Play the Classic Doom Games

You can find an old-school PC which you can interact with in this room. By collecting floppy disks or entering a password, you will be able to unlock and play the original Doom and Doom II respectively!
Check Out the PC Password Here!View Found Collectibles

As you play through the game, you will find collectibles in hidden and secret areas. You will be able to check out all of the collectibles you've earned here! These include weapons, toys, and even soundtracks from previous DOOM games!
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