Mars Core is the 7th mission in Doom Eternal and contains 30 collectible locations (3 Toys, 5 Codex pages, 1 Cheat Code, 2 Runes, 3 Sentinel Batteries, 1 Sentinel Crystal, 2 Albums, 2 Secret Encounters, 5 Praetor Suit Tokens, 1 Slayer Key, 1 Slayer Gate, 1 Empyrean Key, 6 Extra Lives). This walkthrough will guide you to all Mars Core collectibles in Doom Eternal. If you missed something you can get it via mission select.
- 3 Toys
- 2 Codex Pages
- 2 Runes
- 1 Cheat Code
- 3 Sentinel Batteries
- 1 Sentinel Crystal
- 2 Albums
- 2 Secret Encounters
- 5 Praetor Suit Tokens
- 1 Slayer Key
- 1 Slayer Gate
- 1 Empyrean Key
- 6 Extra Lives
All collectibles in this chapter are listed in chronological order. If you miss anything you can use fast travel when it unlocks at the end of the mission to go back everywhere.
Rune #1 – Directly in your main path early on in the mission, impossible to miss (after jumping into the first teleporter).
Extra Life #1 – In the 2nd big enemy encounter (after going outside) it’s floating in the air.
Sentinel Battery #1 – After the 2nd big combat encounter in the outside area you will drop down a hole, turn around and jump across the gap to reach this.
Praetor Suit Token #1 – In the room with the green pistons moving up and down, on a walkway just above on the left side of the room.
Codex #1 (BFG-10000) – After you jump across the pistons and move through a green vent, on the left as you exit.
Extra Life #2 – After getting the BFG-9000 and stepping in the portal to a burning area, it will be on the right side after jumping into a building.
Praetor Suit Token #2 – You’ll have another big fight in an outside area you drop down a hole. To the left of the exit is a cracked wall, punch through it and jump to the opening down below and to the right leading to the token.
Secret Encounter #1 – Just to the left of the previous collectible.
If you have BFG ammo this will kill everything that spawns ahead easily, otherwise using all of your heavy weapons, Rockets, Grenades, Ballista and so on.
Toy #1 (Prowler) – In the next area after riding a short elevator, this will be on your right.
Rune #2 – Directly in your path shortly after the previous collectible, impossible to miss.
Cheat Code #1 (Powerup Mode: Onslaught) – In the room with several tentacles, enter the room on the right to see this cheat location in plain sight.
Praetor Suit Token #3 – In the previous room, enter the doorway on the left and turn left again to climb up.
Album #1 (Doom 64 – Intro) – Across the gap just ahead and up the blue vent, turn around and swing off the pole to reach the secret on the other side.
Extra Life #3 – From the last Collectible turn around and use the hanging bars to jump through a breakable wall ahead. If you miss the wall, you can either restart the checkpoint or drop down to it later from Toy #2 (see 2 collectibles down below).
Secret Encounter #2 – Immediately after the last collectible, drop down to continue, proceed forward and enter the building on the left. Break the vent and jump through the portal to a new area with this encounter.
Immediately kill the imps with a rapid fire weapon, freeze the whiplash then kill it, kill the next imps and use the ballista or rocket launcher to quickly kill the cacodemon.
Toy #2 (Carcass) – From the secret encounter, go up the blue vent and in the next room behind the pillar.
Extra Life #4 – After a big enemy encounter on a pillar during the jumping section, in plain sight.
Praetor Suit Token #4 – From the Extra Life it’s ahead on the right side. Jump-dash to the platform with the sentinel hologram on it (easily visible from afar).
Extra Life #5 – Under a flying island between the last and next collectible.
Sentinel Battery #2 – On the flying island above the 5th extra life is a battery at the top. Jump on the blue vent, turn around and navigate the platform backwards where the battery is.
Sentinel Crystal #1 – As soon as you jump on the previously mentioned blue vent and then land, it’s in the room directly in front of you.
Slayer Key #1, Slayer Gate #1, Empyrean Key #1 – In the next room with many tentacles, there is a small control panel with a switch you can press. This moves an object out of the way ahead. From where you interacted with the console, head to the right to find a pedestal emerging from the floor. From the pedestal you can jump to a breakable vent on the right side to find the key at the end. Then you use it on the gate where the purple circle is on the map. Remember to use your BFG-9000 Super Weapon to make the fight easier.
Album #2 (Quake Champions – Goroth) – Opposite the vent leading to the slayer key, break it to find the secret.
Toy #3 (Pinky) – After dropping down to the next room, look immediately left and smash through the vent, jump on the blue vent here to find this secret right ahead.
Sentinel Battery #3 – Once you land in the core of mars, this battery is immediately on the right after dropping down.
Codex #2 (The Lost City of Hebteh) – Immediately after the previous collectible on the right.
Praetor Suit Token #5 – Just after the previous collectible, after you enter the catacombs on the left.
Extra Life #6 – In the last enemy encounter of the mission floating in the air, in plain sight and impossible to not see it.
That’s 100% of the collectibles you can find in Mars Core of Doom Eternal.
Next Up: Sentinel Prime
For all other Missions, check out the complete Doom Eternal Collectibles Guide.