The trick to finding Orcus, the Aether Worm boss of MWZ, is relatively simple but you’ll need to grind MW3 Zombies to take it on!

Some of the very best Call of Duty Zombies experiences culminate in an incredible boss fight – and MWZ is no exception.

The first-ever Modern Warfare Zombies mode is, for the most part, a take on MW2’s DMZ, but with undead roaming the map. But complete each Act’s missions and you’ll encounter three story events, the last of which has you facing off against a giant Aether Worm!

How to Find the Orcus Worm Boss Fight

Orcus, the giant Aether Worm boss fight in MW3 Zombies, is encountered in the Act 3 story mission, which players can only access after completing all Act 3 missions.

Here are all the Act 1, 2, & 3 missions you’ll need to complete in MWZ!

A Dying Orcus Worm Boss
Credit: MrRoflWaffles

The final Act contains by far the most difficult of the game’s missions, requiring players to grind to overcome one last hurdle before reaching the boss fight.

Then, in the Act 3 Story Mission (the spoiler-filled name of which we won’t mention), you’ll face off against Orcus, the long-awaited Aether Worm boss of MW3 Zombies.

Despite rumors claiming the Worm boss would appear at MWZ’s final Exfil, this is most assuredly not the case.

How to Beat – Tips & Tricks

We recommend having a squad of at least 4 players before taking on the Aether Worm fight. Don’t forget that you can invite other players to join your squad using the Assimilation feature.

Before heading to the icon on your map and using the red smoke to Exfil to Zakhaev’s Stronghold, make sure you:

  • Have strong weapons, and be sure to Pack-a-Punch to at least Level 2 and ideally to Level 3
  • Find a Self-Revive each if possible
  • Drink as many Perk Cans as you can find
  • Have as many squad members as possible
  • Have plenty of spare Armor Plates and a 3-Plate Vest each
  • Apply any Ammo Mods you’re carrying

Then, after completing the initial steps of infiltrating the Stronghold and obtaining the Neutralizer, it’s time for a boss fight.

Orcus’ Weak Point

When Orcus, the Aether Worm, emerges from the ground, you’ll notice that it is glowing purple in several areas along its body.

These are its weak points, which give off the critical hit marker and sounds when shot. Try and get a good angle, and aim for the glowing purple weak points.

Orcus Weak Spots
Credit: MrRoflWaffles

Just be sure to keep your eyes peeled for incoming zombies too. It’s all too easy to get surrounded when your attention is on a gigantic boss.

Aether Worm Attacks

The MW3 Zombies Worm Boss fight has several devastating attacks that could spell disaster if they hit you:

Aether Beam

Orcus will often charge up and fire a powerful purple beam of Aether energy at players. Before it does so, it will reel back and then snap its head forward, like Godzilla using its Atomic Breath.

Orcus Worm Boss in MWZ Zombies
Credit: MrRoflWaffles

It will also aim close to itself, hitting the ground next to it, before moving the beam further out. Therefore, we don’t recommend getting close, as it will give you less time to dodge.

Ground Slam

The Aether Worm will slam its head into the ground, likely downing any unlucky player who happens to be beneath it.

This slam attack can be done over the top of buildings, so don’t consider yourself safe just because you’re taking cover. Thankfully, it doesn’t have too wide an Area of Effect.

Aether Worm Slam Attack
Credit: MrRoflWaffles


The Worm Boss can also bury itself underground and charge towards players. Thankfully, it’s possible to see where the Worm is moving thanks to a dirt cloud, so you can avoid being there when it erupts from the earth.

Be sure not to take your eyes off Orcus for too long, even when dealing with other undead foes.

With a squad to help you, the Aether Worm won’t take too long to dispatch, so long as you’re sufficiently prepared. Luckily, if you do get wiped, you’ll be able to take on the Orcus fight again, simply by activating the Story mission once more.

Thanks to YouTuber MrRoflWaffles for being the one to discover this incredible boss fight, after a 35-hour-long stream on release day! Check out the Zombies pro’s first encounter with Orcus below:

Managing Editor
Max has a wealth of experience in the industry and is a lover of all things video games, situated in Manchester, United Kingdom.
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