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Black Ops Cold War: Zombies – Use Sergei’s Head For A Free Perk | Firebase Z Guide

February 8, 2021 by Kevin Thielenhaus

Get yourself a free perk with this alternate Essence Trap Easter egg.

Say hello to Sergei.

Because there aren’t enough side Easter eggs in Firebase Z… here’s yet another one. Maximizing your time is pretty important in any Call of Duty: Zombies map, and this little Easter egg is pretty easy to pull off. It’ll get you a free perk, and send a whole load of Hellhounds after you. You’ll also need to progress into the main Easter egg quest to do it — thankfully, these steps are pretty easy to accomplish, even if you’re playing solo.

It’s all about Sergei’s Head. This weird key item was once thought to be part of the main Easter egg quest, but it turns out it’ll just get you a big bonus for completing it. If you find this weird zombie head and have no idea what to do with it like I did, then this is what you need. It’s a nice little bonus task you can do while you’re hunting down Mimics.


More Zombies Firebase Z guides:

How To Turn On Power & Pack-A-Punch | Weapon Upgrade Guide | How To Unlock The Ray Gun Wonder Weapon (For Free) | How To Complete The Main Easter Egg Quest | Firebase Z Guide | Secret Song Easter Egg & Cassette Locations | Free Jugger-Nog Teddy Bear Easter Egg


Where To Find Sergei’s Head

Sergei’s Head is key to a side Easter egg quest. It isn’t required for the main Easter egg, but you will need a unique key item from the main quest to actually use this head. To get started, you’ll want to find the head after restoring power.

  • Sergei’s Head Location: Scorched Defense – In the back-right corner, across from the Eyeball Key Item you can acquire for the Ray Gun Wonder Weapon EE, you’ll find the Sergei’s Head Key Item.

When you pick up Sergei’s head, it takes up your weapon slot temporarily and limits your movement. You can’t jump, mantle or sprint while holding Sergei’s head.

Plant Sergei’s head somewhere you won’t forget it — you’ll need to come back for it much later after completing several main Easter Egg Quest steps. Before you can use Sergei’s Head, you need to get the Essence Trapper Device.


How To Get The Essence Trapper Device

The Essence Trapper Device is a key item you get by completing early steps in the Easter egg quest. Here’s a quick and dirty guide to get you to the Essence Trapper.

  • Restore power on the map by recharging the 3 Aether Generators.
  • Talk to Dr. Peck in Mission Control, then talk to Ravenov in the village to gain the keycard.
  • Use the keycard on three lockers and collect the chemicals inside. The chemical lockers are located at: Colonel’s Office, Weapon Storage, and Engineering.
  • Go to the Field Hospital and mix the 3 chemicals. Defeat the Hellhounds that spawn.
  • Place the chemicals in the dispersal device, then place the dispersal device on the air-conditioning unit on the rooftops at the OPC.

Finally, talk to Dr. Peck and go to the Data Center to collect the Essence Trapper. This is a unique key item that works like C4 — throw down the Essence Trapper, then double-tap [Reload] to activate the device.


How To Get A Free Perk

Once you have Sergei’s Head and the Essence Trapper Device, you can complete the side-quest. Follow these last steps to get your perk reward.

  • Grab Sergei’s Head and travel to the Field Hospital. Place it on the Charging Station (near the door close to the Data Center stairs) by holding interact.
  • Throw down the Essence Trap and capture any zombie. Make sure the zombie is weakened to trap it.
  • Place the full trap into the Charging Station next to the head. The head will come to life and tell you the safe code.

Now you can travel to the Colonel’s Office in Military Command and unlock the safe. The moment you open the safe, Hellhounds will spawn — so get out of the room, clear the wave, then grab your free perk from the safe.


More Call of Duty: Black Ops Cold War guides:

Die Maschine Easter Egg Guide | How To Complete Every Step | How To Unlock Pack-A-Punch & Upgrade Guns | Die Maschine Guide | How To Get The D.I.E. Shockwave Wonder Weapon | Die Maschine Guide | How To Upgrade To All 4 Wonder Weapon Variants | Die Maschine Guide

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