Doom Guide: Secret & UAC MarineGuy Locations Guide
Doom has always been home to many secret rooms and areas and the newest one is full of them as well. Finding all of them in a level will unlock you extra weapon points so you can upgrade your guns. Check out this Doom Secret Locations Guide to find all the secrets and the UAC MarineGuy collectibles too.
Doom Guides
Doom Weapons List & Locations
Praetor Suit Upgrades Guide
Find Every Collectible With The Automaps
Doom Secret Locations Guide
The UAC Secrets & MarineGuy Locations
Doom The UAC Secret 1 – The first secret you will find is right after you get the blue key card. Jump up on the crate near the key card and look up to see a green light near a ledge. Jump up to the ledge and grab the collectible for a secret.
Doom The UAC Secret 2 – The second can be found right after the blue key card door. Follow the path down and stick to the left side of the wall. Keep going until you find a metal building you can enter. Enter and go all the way to the bottom of that area and turn around. You should see this when you turn around. There is a doorway with a switch you need to hit. The switch can be located through a small metal opening below the fan, check out the picture below.
It is not the white open door one the left, it is the doorway on the metal part in front of the Doom guy. The white door is what you open when you hit the switch inside. After you hit the switch, go into the room and clear out the enemies for an upgrade point. You can also hit the 2 red switch on the shelf to get a secret inside the secret.
Doom The UAC Secret 3 – The last secret in the level isn’t actually all that hard to find. You can just crawl through the hole next to the collectible or jump across. Here is a picture of where on the map.
Resource Operations Secrets & MarineGuy Locations
Doom Resource Operations Secret 1 – When you restore power to the door switch using the computer, turn around and jump up into the opening. Follow the path to the end and you will get the secret.
Doom Resource Operations Secret 2 – The second secret is when you drop down the maintenance door. Follow the path until you get to a cat walk that leads to two doors. The one on the left is the secret door we are going to open. If you look up you will see a platform above the door. Use the containers that you passed to jump up to the top. Hit the switch at the top and open the door down below. Enter for another secret.
Doom Resource Operations Secret 3/4/5 – The next secrets need you to have the yellow key card. When you have the yellow key card you need to go to the security room and use it to give you access to the area. From the yellow card door jump up the boxes and cross over. On the other side there is a room you can use the key card to enter, that is where you get access. Go outside the room and into the hallway to find a hatch. Go down the hatch and grab the armor upgrade and go out the other hatch. Here you will find the Plasma Rifle and another secret.
Doom Resource Operations Secret 5/6 – Once you have the security access you will need to use the elevator to go back up to where you got the yellow key card. The room to the right of the card will be open and inside is a secret. Follow the vent in that room and drop down on the other side for another secret.
Doom Resource Operations Secret 7 – The next secret is found after the yellow key card door, when you are outside. Near the entrance to the building you will find a single box hat has blood on it.
Climb up that box and then up further. Follow the vent up to the right and at the top look behind you. Jump to the next vent and follow that until you can jump onto the roof. On the roof in the back corner you can find the collectible. You can then use the hatch on the roof to go back down into the building if you want.
Doom Resource Operations Secret 8 – The last secret in the level is right at the end, near the Vega terminal. Instead of using the terminal look left and climb the boxes up to the top. Go through the vent and grab the collectible to get all the secrets.
The Foundry Secrets & MarineGuy Locations
After you spawn in head out to the foundry and jump the gap to the left. Follow that path until you can make a right towards a cart on a platform. Jump onto the platform and pull the lever on there to unlock the Retro Doom Level. It is across the bridge near the pouring lava – Thanks for the help vipLink.
Doom The Foundry Secret 1 – When you reach the room shown in the screenshot above head to the far side, where you see the lava pouring out from the tubes in the wall. Drop down between the 1st and 2nd tubes onto a platform, turn around and you’ll see the MarineGuy there.
Doom The Foundry Secret 2 – This secret is just for some armor but you need it for the weapon point. When you get to the computer that needs a hand to verify, go out the other door you didn’t come in at. This is another foundry part with a missing bridge. Jump to the bottom and follow the green lights for jump points back up but on the other side. When you get to the top you will get the hand. Before you jump off, go all the way to the left and jump into the vent at the end for the secret.
Doom The Foundry Secret 3 – Progress through the level and eventually you’ll grab a Plasma Rifle before heading into a room filled with enemies. On the right side of the room there is a group of crates with robotic arms. Search inside the middle crate for a MarineGuy
Doom The Foundry Secret 4 – This one is in the same room at the second Marine guy. Before you go into the next room, look right and you can see some crates to climb up. Jump to the vent across and you will find a secret and an armor upgrade!
Doom The Foundry Secret 6 – Last secret in the Foundry is in here 😉 You need to jump on the pipes marked with 1, and then jump to the other side and there’s the corridor. Rocket launcher in there. Huge thanks to Kamil Bar for the information and screenshot.
Argent Facility Secrets & MarineGuy Locations
Doom Argent Facility Secret 1 – This is the Doom Retro room for the level. As you are progressing through the level you will enter a hall with lots of blood, gore and demonic symbols. Go back out the door oyu can in and go to the right. Around the corner you will find some supplies and the lever for the retro level is there, behind some barrels.
Doom Argent Facility Secret 2 – You can find the first secret while you are shutting down the Argent Filters. When you get the blue force field, go into the building near there and look to your right. You will see two boxes tacked on top of each other. Jump up on them and then jump higher to get the MarineGuy.
Doom Argent Facility Secret 3 – This one can be found when you are going after the last Argent Filter. There is a haste buff in this room also to help you know what room I am talking about. Go to the bottom of the big room with the blue light and you can find a broken door you can force open. Force it open for the secret and the Automap.
Doom Argent Facility Secret 4 – You actually see this one pretty early but it runs away when you find it. When you get to the first demon spawning thing then you are close. Clear the area and then look down below. Go around the force field and you will see a path that leads down into a jammed door. Duck under the door and you can find the bot and supplies there.
Doom Argent Facility Secret 5 – You can find this one here on the map.
Use the box to get up to the next level and then take a left. Don’t jump the gap but instead follow the skinny path to the right and at the end you can find a MarineGuy.
Argent Energy Tower Secrets & MarineGuy Locations
Doom Argent Energy Tower Secret 1 – Shortly after you begin the Argent Energy Tower level you find some boots that let you double jump. You need to head to the far end of the main room and jump up some ledges to reach a secret. The image above is the platform you need to reach, the secret is just to the right in a small area you can drop into.
Doom Argent Energy Tower Secret 2 – As you reach the area where you have to cross the bridge stick to the left side. A short distance across you’ll see several sets of stairs that lead up to higher levels. Follow it all the way up into a room. From there cross the bridge into another room. This is the secret area with a Combat Support Drone.
Doom Argent Energy Tower Secret 3 – When you reach the end of the bridge in the Argent Energy Tower mission and jump across the gap, drop down to the right and you’ll find a secret area.
Doom Argent Energy Tower Secret 4 – Once you reach the area with the large metallic containers moving around, continue through until you reach the end. Don’t follow the walkway on the left, drop down to the right. Where the reticle is on the image above. Go the end and you’ll see one of the containers that’s not moving. Get on top of the container and you’ll see a small ledge opposite. Way for the moving containers to pass and then jump up there. At the top turn around back on yourself and jump to the higher ledge. Wait for the container to pass again and follow it through the hole. Jump down to the left to find the secret area.
Doom Argent Energy Tower Secret 5 – After clearing the bottom floor in the Tower you will have to scale your way to the top. When you get to the top of the reacter there will be two ramps going up either side. The right side has a MarineGuy underneath. I went up, dropped down and did a mid air jump to get on the railing underneath.
Doom Argent Energy Tower Secret 6 – After you climb the Tower for a bit you will have to fight another Demon army. After you kill them you will need to use the computer to activate the lift machine. There’s a green one right outside the computer room but oyu don’t want that one. Instead go to the other side and use the white light one. Let it take you to the top and activate the switch up there to unlock the Retro Doom room for the level. Take the robot back down, wait for it to lift off again and enter the room.
Kadingir Sanctum Secrets & MarineGuy Locations
Kadingir Sanctum Secret 1 – Progress through the mission until you reach the area with the large green pool of liquid. From there go up the stairs and you will see a flashing green beacon at the top. Turn directly to your left and climb some rocks. You will see a nearby armor pickup further up some more rocks. Climb to get this secret.
Kadingir Sanctum Secret 2 – You can see this secret to the right after the first door but you can’t get there until later. Progress through the level and eventually you’ll loop back around to the starting area but now there will be some floating rocks up to a platform with a skull switch. Click the switch to open the huge door near the beginning of the game. Head through there but don’t go on the teleportation device, instead walk all the way around to the right and you’ll find a secret area and MarineGuy.
Kadingir Sanctum Secret 3 – You can find this one near the blue door, you can’t access it until you can open the blue door though. When you get to the blue door, turn around and jump to the platform across from you. From that platform turn left and jump to the ledge across from you. Now you should be able to see a small floating platform you can jump to, do that and then follow the path up to get
Kadingir Sanctum Secret 4 – Towards the end of the level you will reach the platform with the weapon mod droid. Shown in the image above. Instead of running towards the droid take the left path and you’ll see a small platform to jump down onto for a secret and a MarineGuy.
Kadingir Sanctum Secret 5 – This secret unlocks a special Doom Classic level. Continue through the mission until you reach the area with the massive fight. Minotaur style enemies, witch type things, eyeballs, the works. There’s a huge door nearby with a green icon on it. Don’t go there yet. Near where most of the enemies spawn is a cave. Inside the cave there’s a lever, pull that. There’s also a Skyrim Easter Egg nearby for fans of The Elder Scrolls. After pulling the lever head out the cave and to the right. Jump down to wear you see the armor pickup and you can see the cave into old school Doom near the blood pools.
Argent Facility (Destroyed) Hell On Mars Secrets & MarineGuy Locations
Argent Facility (Destroyed) Hell On Mars Secret 1 – Near the beginning of the level. Progress forward until you have to jump up two circular platforms, after killing one of the giant eyeball enemies. Once at the top follow the walkway around until you see a platform with a column on it, there’s a big 1 written on the column. Drop down to the left of that and explore the gap in the rock, there’s a MarineGuy there and a secret area.
Argent Facility (Destroyed) Hell On Mars Secret 2 – At the start of the level go outside and follow the cat walk up until you run into the demon with the big eyeball. Kill it and then look to your right and jump up the machines there. Now look right and keep jumping up until you end up on another cat walk and follow it. At the end of the cat walk look right and up, that is where you need to get. When you are up there, look behind the crates for a lever to pull. Down below you can access the Retro Doom Level for this mission.
Argent Facility (Destroyed) Hell On Mars Secret 3 – You can actually see this on a distant platform right at the start but you can’t get there until right near the end of the level. Progress through the mission until you reach a room with a hive inside, the lowest level is flooded and has electrical surges happening all over. As soon as you leave that room take a left and then jump down onto the platform opposite. Follow it round to the secret area.
Argent Facility (Destroyed) Hell On Mars Secret 4 – In the main area there is a Rune Trial. If you look over the edge of the Rune Trial location there’s a small ledge with fire on it. Jump down there and then turn to look at the area below the Rune Trial. There’s a very small ledge with a Praetor Token inside. I was only able to jump onto the ledge from above using the In-Flight Mobility Rune. Look at the image above for map location.
Argent Facility (Destroyed) Hell On Mars Secret 5 – This is in the room where you move the crane out of the electrified water. Jump onto the crane and then jump to the right. Follow that around and you will get a weapon mod and the secret.
Argent Facility (Destroyed) Hell On Mars Secret 6 – Right at the end of the mission, inside the room where you collect the Yellow Key Card from the dead enemy. Check above inside the room for a small ledge. Climb up to get the secret area and a MarineGuy.
Advanced Research Complex Secrets & MarineGuy Locations
Advanced Research Complex Secret 1 – Once you get off the tram and defeat the large demon enemy, take a left and you’ll see two entrances. One to a male toilet and the other to a female. Head into the ladies room and look up, there’s a vent in the ceiling. Jump off the sink area and grab on. Follow it through to find the secret area.
Advanced Research Complex Secret 2 – After you use the terminal to remove the blue force field head to where it was located but don’t jump out to the ledges, instead go through the nearby door and open the airlock for a secret area and Rune Trial. There’s also an arcade machine in the corner that you can play, behind all the crates.
Advanced Research Complex Secret 3 – Directly after finding the Rune Trial secret you will have to go left and jump to a ledge. From there look down and left again for a pathway that leads up. Go down there to get a secret and a Argent Cell.
Advanced Research Complex Secret 4/5 – This secret can be found while jumping to the other side after exiting the first airlock. Instead of going into the pipe down below, to to the upper right and follow that up. There are two secrets here, jump into the little cave where the pipes are leading for a MarineGuy. Now this second is a switch that you can see through the fence next to those pipes you used to find the MarineGuy. There is a platform you can jump up to to the left that goes up pretty high. Once you get to the top, look back towards the pipes for the switch you need to go hit. You will need to double jump to make it and even then it will be close. After you hit the switch, go back to the airlock area and the Doom retro level is there.
Advanced Research Complex Secret 6 – This one is still before entering the pipe so don’t go inside yet. If you look up above the pipe you can see a ledge that you can jump to. Do that and follow it around to the Mega Health and the secret.
Advanced Research Complex Secret 7 – Keep progressing through the level and you will eventually come to a fan that will blow you up to the ceiling if you go on it. Go around to the left and deactivate the fan and drop down. Drop below the fan and go through the vent to find a weapon mod bot.
Advanced Research Complex Secret 8 – Now take the fan up to the top and follow the vents all the way through, following the green lights. When you get to the end, take a left and in that room you will find a Praetor Upgrade Point.
Advanced Research Complex Secret 9 – When you are up in the lab area, look for the one marked Prototype Lab 01. Go inside and look up and to the right to see an open vent. Jump up on the machine in the center and then jump into the vent. Follow to the corpse and you will find a MarineGuy.
Advanced Research Complex Secret 1 – You can find this secret right after you find the BFG. Go into the next room and interact with the computer in there. Instead of going straight, go to the right and go through that door. Go through the hole in the wall and you will find a Rune Trial and a secret.
Lazarus Facility Secrets & MarineGuy Locations
Lazarus Facility Secret 1 – The first secret will be when you find the elevator with the body stuck in it. Go around the crates near there and up the vent shaft. At the end you will get the secret and Mega Health.
Lazarus Facility Secret 2 – After falling down the vent for the last secret you will have to clear a room full of demons. After you do that there will only be one way to go. Go through the door and at the end jump up to the ledge. Instead of going forward, turn around and jump into the other vent. Follow that through and you will get a secret and Praetor Suit upgrade.
Lazarus Facility Secret 3 – You can find this secret during the Lazarus Facility level. As you progress through the level you will eventually run into a Weapon Mod bot in a maintenance room. Jump up above and keep going forward until you run into a locked door on the left. Look on the floor and use the hatch below to get inside. This will get you the secret.
Lazarus Facility Secret 4 – This secret can be found inside the area with the huge corpse of a demon sitting on an operating table in the middle. Clear out all of the demons and then move on. Just as you leave the room you will enter an area with 2 green exits on your left and right, both marked Lab Exit. Don’t go down either of those. Inside go directly in-between on another glass-like table covered in blood. There’s a door at the end of it with a switch on the left. Hit the switch for another Praetor Token.
Lazarus Facility Secret 5 – Right after the Demon being operated on you will go through a door you need to force open in order to get through. Clear out all the demons in there and then look on the left. There are these rocks with red letters on them. Go behind those and enter the vents to find a MarineGuy and a secret.
Lazarus Facility Secret 6 – This secret is right after that weird demonic loading screen. Go up the stairs on the right and look for a red light in all the yellow lights. Click the red light and you will get a MarineGuy.
Lazarus Facility Secret 7 – As you move through the mission you will eventually reveal a hidden staircase that you have to go down. Follow the path until you get to a room with a hole in the middle. Jump in and you will get the secret and an armor upgrade.
Lazarus Facility Secret 8 – In the same area you will find the next secret. Jump out of the hole and look to the left of the stair case. Hit the lever and then jump back down into the hole for the Retro Doom room.
Lazarus Facility Secret 9 – The last secret in the level is right after you close the portal. Go through the next door and take a right into the large room with the vending machines. If you look to the right of the vending machines you will see an opening on the wall. Go in there and you will get your last secret.
Titans Realm Secrets & MarineGuy Locations
Titan’s Realm Secret 1 – This one is pretty early in the level. As you progress you will enter a large room with a toxic floor that you are above. Clear the room and then drop down under the bridge into the toxic goop. Under the bridge you can find a skull switch to hit. This will open up a door on the right side in the toxic goop, your secret is inside.
Titan’s Realm Secret 2 – This secret is in the very next area after the toxic goo area. From there head into the next area, take a right and then a left and follow the path to the end room. You’ll see a red symbol on the back wall of the room so you know you’re in the right one. At the top of the small stairs when you enter there’s a hidden switch, it’s on the left as you walk towards the room. Clear out the demons and the switch opens. Hit it and then walk back towards the way you came in but take a left, the wall is now open.
Titan’s Realm Secret 3 – You can find this secret after you go through the first green portal. You will be in a large room with a bloody floor after you come through. Clear out all the enemies and then go all the way up the stairs. At the end of the path you will find your MarineGuy.
Titan’s Realm Secret 4 – The second MarineGuy can be found right after you take the second green portal, same area as the Automap. Go into the room and take a left towards the blue door. Look left from there and take the yellow pad up. Now jump across the gaps and follow that to the end for the MarineGuy.
Titan’s Realm Secret 5 – Keep going through the mission until you reach a room with a small bridge leading to a door, there’s a large concrete pillar that keeps falling onto the bridge. Clear the room and then climb the pillar to activate the switch at the top. When you’ve activated the switch head back to where you entered the room, there’s now a level right next to the stairs. Pull the lever and climb the stairs and then take a right back into the toxic room. On the right hand side you will see a button that lets you enter and unlock another Classic Doom level.
Titan’s Realm Secret 6 – Keep going through the mission until you reach a room with a small bridge leading to a door, there’s a large concrete pillar that keeps falling onto the bridge. After you clear the area you can take a green portal to another area of the map. Take the first left path you come across after the warp and you will find the last secret and a Mega Health Pack.
The Necropolis - The Crucible Secrets & MarineGuy Locations
The Necropolis – The Crucible Secrets 1 – This is the Doom classic level in the area. You can find the switch for the door in the same area that you find the yellow skull. Near the portal there’s this tiny rooms with fire in them. In the one to the right you can find the switch. Go back down the hall you came in from and you can find the retro room.
The Necropolis – The Crucible Secrets 2 – Progress through the mission until you activate both the switches behind the blue and yellow doors. Eventually you will have to drop down far below. When you drop down you’ll see a large skull over the door ahead. Just before you get there turn back and look below for a floating platform with a MarineGuy on it.
The Necropolis – The Crucible Secrets 3 – Missing
VEGA Central Processing Secrets & MarineGuy Locations
VEGA Central Processing Secrets 1 – The first secret is early in the level. Keep moving forward until you get outside. Keep progressing and eventually you will see some fire below and ahead to the left. Instead of heading left check up and to the right for a door. Enter go to the right, then left. You’ll see a MarineGuy sitting on the edge.
VEGA Central Processing Secrets 2 – Continue through the mission until you enter a door with “Clean Area” written above. It’s after the large room with the two switches. Go through the door and then through the next door you see, you should be inside a room full of terminals and a couple of holograms. Search the left side of the room for a hatch in the floor that you can interact with. Go down the hatch, past the guy with the blue key and then into the door on the left. Automap is inside.
VEGA Central Processing Secrets 3 – When you reach the room with the Elite Guard, don’t drop down to the next secret just yet. There is a lever behind the boxes that the Elite Guard is leaning against. Hit this to unlock the Classic Doom level.
VEGA Central Processing Secrets 4 – Directly after secret 3. Head into the next room to find a Praetor Token. To the left there’s an open hatch you can drop down, it’s a long drop. When you drop down head to the right and walk to the edge of the ledge you’re on. Look ahead and below and you’ll see another MarineGuy and a secret.
VEGA Central Processing Secrets 5 – Carry on through the level until you have to jump down onto a tram to reach the next area. When you jump off the tram there’s a huge room filled with enemies and pickups. Clear it all out and then head to the far end of the room. Your objective tells you to get on an elevator to go up, but don’t yet. Go to the left of the elevator and look below it, there’s a secret there.
Argent DNur Secrets & MarineGuy Locations
Argent D’Nur Secrets 1 – Proceed through the mission until you reach a huge area with 2 massive statues and a beam of red light in the distance. Walk down and to the right and you’ll see a skull switch. Flip the switch and then go to the other side to jump up onto a stone and back onto the ledge you came from. Just ahead to the right is a secret area that’s opened with BFG ammo.
Argent D’Nur Secrets 2 – This is the Doom Retro room. As you pgoress you will run into the red laser things that shoot into the sky that you need to disable. After you disable the first one, go down to where the figure is pointing and hit the skull switch. This will open a door down below to the left. Go into there and you will see some blood on a rock and below that is a switch. Hit that switch and then go right to get the room.
Argent D’Nur Secrets 3 – Same area as the one before but instead of going right go left for BFG ammo and Fuel.
Argent D’Nur Secrets 4 – The next secret is in the area with all the lava and demons, right after the first red laser you disable. After you kill all the enemies go up towards the stairs and you will see a whole in the stairs. Drop down and behind that you can find your first MarineGuy.
Argent D’Nur Secrets 5 – Last secret is past the second laser you disable. You will drop down into a hallway that has a door on the left locked. Go down the hall and on the right side you can find the switch for the door. Return to the door and enter for the last secret.
We’re updating this as we go so if there’s any missing or we haven’t reached your level yet, we’ll have it updated asap. If you can help fill out some details for any we’ve missed, leave a comment. Huge thanks to everyone who left a comment to help us fill out the guide!