How to Solve the Serum Puzzle in BO7 Zombies

Finding all six Serum pieces in Ashes of the Damned can be tricky, as is figuring out the final Serum puzzle. If you’re aiming to complete the Ashes of the Damned easter egg or unlock the DG-2 Turret upgrade for Ol’ Tessie, it can feel overwhelming. Fortunately, we’ve created a clear, step-by-step guide to help you collect all six Serum parts and quickly solve the puzzle in Black Ops 7 Zombies.

All Serum Parts Locations in Ashes of the Damned

Serum Part #1 – Powder of the Forgotten

To make the Powder of the Forgotten, you’ll need the Necrofluid Gauntlet (a special weapon) and the Wisp Tea perk. You can find Wisp Tea at the Zarya Cosmodrome, or earn it by finishing the twins Easter egg at Vandorn Farm (click here for details). Once you have Wisp Tea, go to the Tailor Shop in the eastern part of Ashwood, right next to Vulture Aid. Inside, you’ll find a mirror that Wisp Tea can break. Activate Wisp Tea by damaging zombies, then simply get close to the mirror – it will interact automatically.

Let’s get the Necrofluid Gauntlet! It’s a long quest, but we’ve created a simple, step-by-step guide to help you get it. Once you have the gauntlet, return to the mirror in Ashwood and shoot it. This will cause the Powder of the Forgotten to fall to the ground.

Serum Part #2 – Widow’s Lantern

To find the serum component, start by going to Blackwater Lake. Once there, enter the Cabin and go downstairs to the kitchen. The Jar of Spores you need is in a cabinet under the sink on the south wall – simply interact with the cabinet to collect it.

Now that you have the Jar of Spores, head to Vandorn Farm. Just outside the farm’s main gate, you’ll find a dead horse with mushrooms growing on it. Examine the horse, and a red bulb will appear. After waiting three turns, the spores will grow, and you’ll be able to collect the Widow’s Lantern.

Serum Part #3 – Mysterious Limb

The Mysterious Limb is a special item that appears only after you defeat Zursa, a tough zombie bear. Zursa starts appearing from round 16 onwards. To beat her, you need to use the Beam Attack from Ol’ Tessie. First, you’ll need to get Ol’ Tessie upgraded at the garage in Ashwood by defeating the Cook at Reba’s Diner (Exit 115) and using the Freezer Key to unlock the southwest freezer. You can damage Zursa with any weapons, but finish her off with the Beam Attack – this will cause her to explode and drop the Mysterious Limb for you to collect.

Serum Part #4 – Ravager Eyes

You can get Ravager Eyes after defeating a Ravager enemy. These enemies show up randomly during gameplay, or specifically during Max Ammo rounds, and they move very quickly on all fours. To get the Eyes, lure a Ravager to one of the Saw Blade traps scattered around the map—there’s one near the Barn at Vandorn Farm. Activate the trap, let it eliminate the Ravager, and you’ll collect the Ravager Eyes, earning 2,000 Essence in the process.

Serum Part #5 – Hoard Husk Chunks

To obtain Hoard Husk Chunks, you’ll first need to upgrade Ol’ Tessie with the Abomination Carcass. Here’s how: go to Reba’s Diner at Exit 115 and defeat the Cook zombie, who will drop a Freezer Key. Use the key to open the southwest freezer in the kitchen and retrieve the Abomination Carcass. Then, take the Carcass to Ol’ Tessie’s garage in Ashwood and use it to unlock the Abominations Head Beam Attack.

While driving Ol’ Tessie (with the Abomination Heads equipped), explore the areas between locations where zombies constantly appear. Keep an eye out for a randomly spawning purple-glowing plant. When you find one, use the Beam Attack (R1) to destroy it, and it will drop Hoard Husk Chunks that you can collect. Be cautious when exiting Ol’ Tessie, as the zombies in these areas are very aggressive.

Serum Part #6 – Human Bones

You can find the ‘Human Bones’ item at Vandorn Farm, inside the Barn. To get it, you’ll need a Combat Axe and a Molotov cocktail, both of which are available for free. You can find a Combat Axe in the kitchen of Reba’s Diner near Exit 115, or by completing the Mr. Peeks axe-throwing challenge. Once you have the axe, go to the Barn and throw it at the right foot of the hanging corpse – the one suspended by its wrists. This will cause the foot to fall off, allowing you to obtain the item.

Okay, so I figured out how to get human bones! You need to find a corpse – once you’re standing right next to it, toss a Molotov cocktail at the foot you just cut off. You can make those at the crafting table in the barn, or thankfully, there’s a free one near Ol’ Tessie’s garage in Ashwood. After the flames die down, the foot turns into actual human bones you can collect. It’s kinda gruesome, but it works!

How to Solve the Serum Puzzle in Ashes of the Damned

Once you’ve collected all six Serum components, travel to the Zarya Cosmodrome. From there, head southwest to Yuri’s Lab. Inside, you’ll find the Serum parts in individual bowls, along with some lab equipment. Start by interacting with the Powder of the Forgotten in the fifth bowl, which will cause the vials to release smoke. When the smoke clears, three symbols will appear on the chalkboard – these are words written in the Pigpen cipher. Don’t worry about decoding it yourself, as we’ll provide the translations. You need to interact with the correct bowls in a specific order: first the bowls with the top symbols, then the middle symbols, and finally the bottom symbols. If you get stuck, codzombiessolver.com can help, but we’ve translated the symbols for you in the image and text above.

> – Human Bones (1st bowl)
L –Hoard Husk Chunks (2nd bowl)
C – Widow’s Lantern (3rd bowl)
C. – Ravager Eyes (4th bowl)
L. – Mysterious Limb (6th bowl)

Once you’ve activated the three correct bowls in the proper order, the vials will release red smoke. You’ll then need to interact with the central vial to give a sample of your blood. This will trigger a lockdown where you’ll have to fight off zombies, but remember that your health won’t automatically recover. To heal, use the primary fire of the Necrofluid Gauntlet, then reload—it will absorb health from any zombies you defeat. Once you survive the lockdown, the puzzle will be solved!

2025-11-17 17:06