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How To Do The Safe Easter Egg On Firebase Z (Free Random Perk & All Sergei Head Locations)

In addition to the main easter egg, Firebase Z is full of side easter eggs. One of the side easter eggs is called the 'Safe Easter Egg,' and as the name suggests, it involves opening up a locked safe.

Upon opening up the safe, you will get a random free perk from the seven available perks and C Cipher, for story and cipher lovers. To perform this easter egg, you must turn on the power and build the pack-a-punch machine. Feel free to check out our complete guide on how to do that.

This easter egg also requires you to do the first step of the main Firebase Z easter egg. We will go through that as well. We also have a complete video guide for you to follow along if you prefer a more "visual" guide. The below guide continues assuming you've already turned on the power.


Video Guide

The Serums

The first step of the main easter egg is to get the serums from three different lockers. These lockers are scattered around the Firebase Z map and can only be unlocked using a specific keycard obtained from Ravenov.

To obtain the keycard, you must first go and talk to Dr. Peck in the Mission Control building with one of the Aether Reactors.

When you finish talking to him, Ravenov will call you back to the spawn village. Go back to Ravenov and talk to him.

Once he finishes talking to you, he will give you his keycard ID. You can use this keycard to unlock the lockers having serums in them.

Locker 1

The first locker is in the Equipment Storage building right across the Atrium at spawn. It is the same building with the purple arrow on it. Instead of going upstairs, head inside and look to your right to find a locker with a keycard slot on it. Interact with it to unlock it and get your first serum called 'Compound S16.'

Locker 2

The second locker is in the Firebase. Go through the portal on the balcony, and you will reach the Helipad area of the Firebase. Go left through the gate and straight into the Engineering section under OPC. You will find another locker in here. Unlock it using the keycard to obtain a serum called 'Compound 36.'

Locker 3

The third and final serum is found in Colonel's Office in the Military Command Control Room. This serum is called 'Compound P65.'

After retrieving all three serums, make your way to the Field Hospital just past the Barracks. In the Field Hospital, you will find a Chemical Mixture on one of the tables.

Interact with it to mix all your collected serums. It'll take a couple of seconds, so give it some time. As the serum mixing comes to an end, some hellhounds will spawn near you. So, be careful when going through this process.

After taking care of the hellhounds, go back to the same table and interact with it to transfer the serum mixture into a Gas Dispersal Device.

After transferring, you will get an option to pick up the Agent Delivery System.

Pick it up, and then make your way back to the OPC. Go to the OPC roof section, and you will find an air conditioner directly above Dr. Peck's locked room.

You will get an option to interact with it and place the Agent Delivery System on it. Place the system on it and return to Dr. Peck to talk to him once again.

You will notice that Dr. Peck's room will be filled with a pink/purple gas. Now, you will need to sit through a long conversation and witness Dr. Peck's impeccable dance skills.

After he is done with his dance, he will tell you to go to the Data Center. This step is actually part of the main easter egg, but we don't need to go any further than this.

Head over to the Data Center, and you need to approach the Memory Transference Station. Once you get close enough, Dr. Peck will start speaking about the station. Wait for him to finish speaking, and then you will get an option to interact with it to unlock it.

Once unlocked, you will be able to grab an 'Essence Trap' device.

Grab one device and then find any random zombie to trap into the device. To trap a zombie, you need to first lower the health of a zombie to almost zero and then throw the device using your Tactical Equipment bind-key.

Once thrown, activate it just like you would detonate your C4 explosives, and the zombie will be sucked into the device. You must do it when the zombie is close to the device.

You will notice that the device will turn purple upon successful capture of the zombie.

If the zombie is not captured, the device gets destroyed, and you will need to return to the Memory Transference Station to get another one. You can only keep the zombie in the device for 3 minutes, after which the zombie will be released, and the device will get destroyed.

Once you have the zombie, run back to the Field Hospital again, and this time interact with another table with a metal plate on it. When you interact with it, the essence trap will be slotted into a device on the table. You are now done with the main easter egg part of this side easter egg.

Sergei's Head

The next step is to find Sergei's head. Sergei's head is used as a medium for the zombie memory to be "spoken" through. Sergei's head has six fixed spawn locations, and in each game, it can spawn in any one of the six locations.

There are two fixed spawn locations in each one of the defense areas of the map: Jungle Defense, Rocky Defense, and Scorched Defense. The locations are as follows.

Jungle Defense

  • Head Location 1
  • The first head location in the Jungle Defense area is to the very far left of the defense area. Go all the way down beyond the sandbags, and you will notice a huge crater in the ground in the middle of the two-way separator. The head will be next to a small palm tree. It will be quite hidden, but the yellow border of the head gives its position away.

  • Head Location 2
  • The second head location is to the very right side of the Jungle Defense but within the defense lines just behind the right turret gun. It will be next to a green barrel and some sandbags.

Rocky Defense

  • Head Location 1
  • The first head location is to the far left of the Rocky Defense area, between some green barrels and sandbags in the corner. The head will be inside the bush.

  • Head Location 2
  • The second head location is to the far right of the Rocky Defense area, just under the staircase leading to the Weapons Lab.

Scorched Defense

  • Head Location 1
  • The first head location is to the far left section of the Scorched Defense area. You will find it under the wooden platform leading up to the defensive wall.

  • Head Location 2
  • The second head location is to the rightmost section of this defense area, where you also find Dimitri's body to get his eyeball for the RAI K-84 wonder weapon easter egg. You will find the head lying on the sandbags just opposite the destroyed tank.

    Once you have the head, pick it up, and bring it back to the Field Hospital. Note that when you are holding the head, you won't be able to interact with anything, nor will you be able to kill zombies. Every time you need to kill a zombie or interact to open a door, you will need to drop the head.

    Return to the Field Hospital and interact with the same table where you inserted the essence trap to put the head on the metal plate. The memories from the essence trap will transfer into Sergei's head, and it will speak out a sequence of numbers. These numbers are the code to the safe in Colonel's Office.

    You do not have to remember these codes, just wait for the head to finish speaking and make your way to Colonel's Office. This time, you will notice that there will be a prompt to unlock the safe when you approach it.

    Unlock it, and you will find a random perk and a C Cipher inside.

    Note that be prepared to face A LOT of hellhounds. Given how small the office is to deal with these hounds, it would be best if you jumped out of the office window and dealt with these hounds in an open area. You can easily die from multiple hounds as the dogs' combined damage, and their incendiary damage is way too high for you, even with the Jugger-Nog perk.

    And that concludes our safe easter egg.

Hassan Sajid

Hassan has always loved Battle Royale games, right from the start of his gaming career. He has played PUBG and Fortnite extensively and as a fan of the Call of Duty series, Warzone is a no brainier for him. His favourite Call of Duty title is Modern Warfare 2. Hassan uses his in-game experience to create guides and videos that are aimed at helping other Warzone players become better. Hassan is also on LinkedIn.


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