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Call of Duty Cold War Zombies: Firebase Z Easter Egg Walkthrough

Firebase Z will keep you here for the long haul, so strap in.

The brand new Zombies map in Call of Duty: Black Ops Cold War, Firebase Z, has the whole zombie-slayin’ world talking. It’s a big map, and a really nice change of pace. There’s even a new easter egg in Firebase Z, which was figured out by community members within just two hours. So, here’s our walkthrough of how to do the Firebase Z easter egg.

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How to complete the Firebase Z easter egg

In order to complete the Firebase Z easter egg, you’ll need a whole lot of patience, and preferably a couple friends ready and willing to help you out. A few steps are extremely challenging, so you’ll want to get as far as possible as quickly as possible. Without further ado then, let’s get to our step-by-step guide on how to complete the Firebase Z easter egg.

Turn the power on and get the Ray Rifle Wonder Weapon

In order to complete the easter egg, you’ll need the Firebase Z Wonder Weapon. We’ve put together a full guide on how to obtain the Ray Rifle, but here’s a quick rundown if you just need a reminder:

  • Get the blueprints from the Weapons Lab
  • Go to Scorched Defense and take Kuhlklay’s eye
  • Scan the eye on the Weapons Lab PC
  • Find the diary in one of the Barracks lockers
  • Kill a Mimic that spawns and pick up Barrel Assembly
  • Kill a Mangler to get the Uncharged Power Cell (the Mimic and Mangler may not spawn immediately)
  • Charge the power cell in Weapons Lab (this takes a round or two)
  • Interact with the PC in Weapons Lab and memorise the dartboard positions highlighted
  • Go to the dartboard in village’s bottom floor, shoot the three numbers highlighted, then shoot the bullseye
  • Go back to the Weapons Lab blueprint and assemble the Ray Rifle

This is an early step, but you might as well do it as soon as possible because the Ray Rifle is actually pretty damn good if you’re hitting headshots.

Talk to Ravenov and Peck

After assembling the Ray Rifle, go to the village and talk to Ravenov, just next to the Pack-A-Punch machine. When he’s said his piece, go to see Peck, who is behind a glass wall in the Mission Control room. When he’s done talking, go back to Ravenov and he’ll give you a keycard. Don’t worry - Peck is an absolute chatterbox, but at this point, zombies don’t seem to target you. How considerate of them.

Get truth serum

Take the keycard to a few places around the map. They’re big tall lockers with keypads on them. Make sure you grab the little bottles inside the lockers in the following locations:

  1. Equipment Storage - in village across the road from the Pack-A-Punch room
  2. Colonel’s Office - upstairs from Military Command Control Room
  3. Engineering Room - just through the door to the little tunnel off the side of the room
An example of an openable locker in the Firebase Z Colonel's Office.

Now, you need to head over to the Field Hospital and make the truth serum from the three compounds you’ve collected. To do this, interact with the table on the left side of the main door with all the tubes and gear on it. When you do this, hellhounds will spawn, so hold them off and then grab the serum.

Use the truth serum on Peck

Once you have the serum, go back to where Peck’s office is in Mission Control. Now, put the serum on the air conditioner above his office. This is quite tough to find, so starting from looking through Peck’s window:

  1. Turn around and head up the stairs so you’re on the platform directly above his office
  2. Go out the doorway towards the OPC
  3. Turn left before reaching the OPC stairs and hop over the railing
  4. The air conditioning unit is a large box on your left

Now it’s time for Peck to have another big long talking session. He’ll start talking and telling the truth and dancing. You have to wait this out, but zombies should stay away for the moment. Talk to him until he lets you know how to open the portal.

Peck talks a LOT while under the influence of a truth serum.

Trap Mimics using the Essence Trapper

This step is extremely finicky, I’ll be honest. What you have to do is go to the Data Center and pick up an Essence Trapper. You get these from the memory machine over near Speed Cola.

In this step, you have to whittle Mimics down and capture them while they’re on low health, like Pokemon. Put the traps on the ground as a low-health Mimic is running towards it and activate it by double-tapping Square (or X on an Xbox controller). This’ll suck the Mimic in, and you can deliver it back to the memory machine.

However, it’s not that simple. You need three specific Mimics from three specific locations in order to get the codes for the quantum mainframe, as well as the dimensional tracker ID tag. In short, you need to trap Mimics that have spawned in the following locations:

  • Peck’s office (upstairs from the Pack-A-Punch room)
  • Colonel’s Office (near Jugger-Nog)
  • Sky Bridge

In all honesty, when you’re fighting mountains of zombies, this stage is an absolute pain, but you’ll know you’ve got a correct Mimic memory upload when Weaver tells you. Also, the Mimics only have to have spawned in those locations, rather than be captured there. Once you have all three, a floppy disc will come out of the memory machine. Pick it up and go to the Planning Office, interacting with the machine with all the screens.

The floppy disk from capturing mimics finally emerges from the memory machine in Firebase Z.

Talk to Peck and Ravenov again

Go to Peck’s office and talk to him again. Then, head over to Ravenov and get the code for the Aethermetre locker. Don’t worry, you don’t have to memorise it, just go back to Peck and open the locker that’s just to the left of his door.

Now, head to Scorched Defense and pick up a shovel in the left bunker. You’ll need this to carry out the next step

Collect three Aetherium crystals

You’ll need to dig up three aetherium crystals now. They can be found in these locations:

  1. Open Lot (through the left gate in Firebase) - the correct crystal is the one without smoke billowing. If you get it wrong, boss zombies spawn
  2. Jungle Defense - dig it up and you’ll have to survive an onslaught of zombies while remaining in a specific area
  3. Barracks - just past the barracks, on the way to the Data Center, you’ll find the final container. This one moves around the map, so get close and use the grenade launcher fire mode of the Ray Rifle Wonder Weapon to keep it in place and grab it

Once you have the crystals, put one in each of the reactors you activated when turning the power on at the start of the game. You can then watch a cutscene at the OPC.

Final stage

You’re nearly done! After starting this stage, you’ll be thrust into a big boss battle, so don’t do it until you’re all perked up and ready.

Head to the Planning Office and interact with the computer. You’ll need to shoot down the satellite with a question mark as its description.

Now it’s time for the final boss fight. Focus your fire on the boss to take it down as quickly as possible, but keep on the move to avoid getting overrun by Manglers and Mimics. It’s a rough one, but as long as you keep the damage coming, you’ll be able to push through and win. Don’t get too close when Orda starts swinging, and make sure you hit glowing weak spots to boost your damage. When this is done, take a breather, have a big glass of water, and enjoy the final cutscene.

That’s all for our Firebase Z easter egg guide! If you want a hand on the best loadouts to make it far in the easter egg, our best Zombies loadout page is all you need to help you out, and for more advice on other modes like multiplayer, we have guides to check up on, including the best guns in Call of Duty Cold War.

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