Once you’ve collected at least two Sentinel Batteries, be sure to explore the Fortress of Doom between levels to unlock upgrades as the story progresses. These include:
The eight unlockable upgrades can be found in the far corners of your base. As we mentioned above, each of them requires two Sentinel batteries, so be sure to plan accordingly. The same applies to the three Doom Slayer skins, although it’s worth mentioning that these aren’t the only ones you’ll unlock throughout the game.
A modernized version of the old leather. It is located exactly on the opposite corner of the main terminal.
Unlocks the Doom Slayer suit from Doom 2016. It can be found on one of the side ends of the map, separate from the fortress.
Unlocks a classic outfit that appears during the main campaign. It can be found on one of the side ends of the map, separated from the fortress.
Doom Eternal Sentinel Battery Locations
Outside of the specific Sentinel Batteries mission challenge, here is where you can find all of the Sentinel Batteries locations within the missions themselves:
Exultia Sentinel Battery Location
This one is really easy to find. Just before you jump to the portal and the new section, be sure to pick up this Sentinel Battery.
Cultist Base Sentry Battery Location
Another easy grab. You’ll find it as you head to the quest marker just in the left corner.
In the first open-air arena, get close to the edge and look at the huge ship in the sky. Look to the right and you will notice a platform in the distance, head over there and hit the cracked vent.
Once inside, hit the mechanism and the doors surrounding the bounce platform beneath the arena will open. Jump off the ledge and use your dash to get back inside, approach said platform and once you’ve gained enough height, double jump or run to reach the Sentinel battery.
Doom Hunter Base Sentinel Battery Location
After finishing the first arena of the level, head to the center of the map. From there you can destroy a vent and get to the other side to pick up a Sentinel Battery.
In the area where you pick up the red keycard, be sure to turn to the right side and grab an extra Sentinel Battery to use on the Fortress of Doom.
Once you’re on the second floor of the citadel, where the massive structures rise and fall, hop on the one on the left and turn around to pick up another Sentinel Battery.
Super Gore Nest Sentinel Battery Location
After heading towards the destroyed buildings once you’re done traversing the lava pools, you’ll come across a Sentinel Battery.
There are many collectibles that require you to have all three keys, and this is one of them. Go back to the large outdoor area with the huge meat structure in the middle, unlock it and use the bounce pad to gain height.
There is a destroyed building that appears to be covered in tentacles, jump down there and follow the path below to find a Sentinel Battery.
In the acid-infested underground area, take a detour around the corner and climb onto the platform to get a Sentinel Battery.
Arc Complex Sentinel Battery Location
As you move towards the east turret shot and come across the inner room with the balconies, go up the stairs and jump across the room to get a Sentinel Battery.
There is a second Sentinel Battery located in an isolated corner as you move towards the west turret.
Just before entering one of the last moments of the Arc Complex, where the floor is covered in purple, jump up and grab another Sentinel battery.
Mars Core Sentinel Battery Location
As you go through the underground section with those long hallways, turn around and head towards the other end by jumping on the floating platforms. A new Sentinel battery awaits you there.
Once you’re out in the open witnessing the huge hole you just made in Mars, make your way around the floating platforms and pick up the second Sentinel Battery in this mission near the tower.
There’s another Sentinel Battery up for grabs after using the escape pod, so don’t miss it!
Taras Nabad Sentinel Battery Location
Another easy collectible that will be available immediately after starting the mission. To do this, drop from the first bridge to the platform below and hit the wall to collect the Sentinel Battery.
Immediately after obtaining the Titan Crucible, you will come across a hole in the ground. Around it, be sure to pick up the Sentinel Battery.
In the first large outdoor area of the game, you’ll see a Sentinel Battery locked behind bars. To unlock this, go to the far corner of the area and hit the statue in the knee with a crack on the side.
Activate the button and you will now be able to access a previously locked room on the second floor. Hold on to the wall, jump and hit the chains, and then proceed to grab the object.
Looking for more things to find? Our complete list of Doom Eternal secret locations may be helpful.