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Borderlands 4 Guide

How to Unlock the Legendary Onion Armor Shield

Shields
Legendary Loot
Updated on Sep 19, 2025
Sep 19, 2025

Overview

Onion is a Legendary Armor Shield with an incredibly powerful passive effect. Its Shallot Shell ability grants a two-second Immunity to all damage whenever one of your Armor Segments break.

With a total of four Armor Segments, this can translate to eight seconds of Immunity during tense fights, all while recharging throughout combat. However, just keep in mind it won't save you from one-shots!

borderlands 4 onion armor shield

How to Unlock

Unlock Location:

  • Obtaining the Onion requires you to defeat Sludgemaw during the side quest known as 'All Charged Up', which can be found as one of the faction missions in the Fadefields.
  • You may also receive the Kickballer from the same boss.

borderlands 4 sludgemaw location

Farm Method:

  • Use Moxxi's Big Encore Machine to re-challenge Sludgemaw.
  • Farm until the Onion drops.

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