All USB stick locations to find the Greylorm boss in Modern Warfare 3 Zombies

Call of Duty: Modern Warfare 3 Zombies contains intriguing hidden challenges, one of which involves discovering and collecting four USB sticks. This step is critical in summoning Greylorm, a formidable giant red worm. Obtaining the USB sticks alone is insufficient; a specific process must be performed to encounter this powerful boss.

Defeating Greylorm solo is a challenging endeavor. Hence, a proper squad and powerful gear are required. However, the efforts are well rewarded with exceptional rewards. This article will provide step-wise guides on how to find the USB sticks and what you must do to find and defeat the Greylorm boss in MW3 Zombies.

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How to find the four USB sticks in Modern Warfare 3 Zombies?

Locations of the USB sticks (Image via Activision)

To locate the USB sticks in MW3 Zombies, initiate a zombie match and open your Tac map upon deployment.

Identify the "F" shaped building in the H2 map coordinate or the rectangular building in the C1 map coordinate, and proceed to any of these locations.

Collecting a USB stick (Image via Activision)

On the second floor of the designated building, discover a room with a wall-mounted map of Urzikstan surrounded by four pictures. Each image corresponds to a Tac map location where USB sticks can be found.

Match the locations on your Tac map, then travel to each to find a UAV tower. Interacting with the UAV tower will result in getting hold of a USB stick, with each location offering a different variant termed Alpha, Bravo, Charlie, and Delta.

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How to summon the Greylorm boss in Modern Warfare 3 Zombies?

Activating a Refractor (Image via Activision and YouTube/MrDalekJD)

After collecting all four USB sticks, consult your Tac map again and pinpoint two Ammo Cache in the H3 map coordinate. If these are not there, explore alternative locations where two distinct Ammo Caches are close to each other.

Travel to the designated location, where you will find four Refractors near the Ammo Caches. Exercise patience and allow the Aether Storm to pass by, which will activate the Refractors.

Now, approach each Refractor and insert the USB sticks. As all the USB sticks are placed, the giant Greylorm boss, similar to the Orcus boss but far more powerful, will emerge from the ground.

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How to defeat the Greylorm boss in Modern Warfare 3 Zombies?

Facing the Greylorm boss in MW3 Zombies (Image via Activision and YouTube/MrDalekJD)

Facing the formidable Greylorm boss within the Aether Storm necessitates strategic planning. Make sure you have plenty of gas masks to help you navigate the storm's hazardous conditions. Before summoning this formidable foe, gather a capable squad, each armed with a powerful weapon, and Pack-a-Punch your weapon to level 3.

Drink various Perk-a-Colas like Deadshot Daiquiri, Jugger-Nog, and Stamin-Up to increase your chances of success. Arm yourself with an adequate supply of grenades, self-revives, and a wonder weapon.

Coordination with your team is essential; therefore, assign distinct roles, such as one member to tackle the attacking zombies, another focusing on the boss, and the third attracting the boss's attention while evading its assaults. The third player, in particular, should use Stamin-Up to increase speed, allowing for more efficient evading of the boss's attacks.

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What are the rewards for defeating the Greylorm boss in Modern Warfare 3 Zombies?

Rewards for defeating the Greylorm boss (Image via Activision and YouTube/MrDalekJD)

Upon successfully defeating the Greylorm boss, you may expect many outstanding rewards, including one of the three desired legendary schematics and other rare items. The potential legendary schematics include:

• Flawless Aetherium Crystal
• The Scorcher Case
• Legendary Aether Tool

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