The Primordial Vault: Carcadia Burn mission in Borderlands 4 challenges you to storm an ancient Eridian vault hidden in Carcadia Burn. Inside, you’ll battle through relentless waves of enemies while navigating the shifting arena. This guide will walk you through the objectives, provide tips for surviving the onslaught, and detail the rewards waiting at the end.
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Primordial Vault: Carcadia Burn Walkthrough
How to Start the Primordial Vault: Carcadia Burn Quest
To begin the Primordial Vault: Carcadia Burn mission in Borderlands 4, you must first collect all three Vault Key Fragments.
Next, you must locate the Vault Door, which can be found southwest of Crumblehall in the Grindstone of the Worthy.

Once you’ve found the Vault Door, place the Vault Key Fragments into the pedestal at the base of the broken arch.

Once inside, interact with the pedestal to officially start this mission!
How to Complete the Primordial Vault: Carcadia Burn Quest
A murderous array stands ready for you, Vault Hunter. Can you beat the odds and triumph?
Move toward your end; it might sting a little
Take the orange jump pad and eliminate all nearby enemies.
Reach the place where no soul survives
After the fight, use the next orange launch pad to refuel at the station. Once ready, launch again to face another wave of enemies—defeat everything in your path!
Progress onward… the end lies ahead
Advance to the next trial and clear out the enemies. When most are defeated, The Chisel will appear. A purple barrier shields this enemy. Destroy the Vile Ordonite, a pink orb it fires, to break the shield and deal damage to The Chisel.
Cross the threshold to certain death
Once the battlefield is cleared, take the launch pad to a pit stop area with vending machines. Stock up, then prepare for the boss fight ahead.

You’ll face Primordial Guardian Radix, a foe two levels stronger than you, with a Shield bar and two Armor bars. This boss mainly does electric attacks. During the fight, it will coat the ground with electricity. Make sure you are standing on one of the rocks in the area to avoid it or stay in the air by gliding long enough until it goes away.

During the fight, some adds will spawn around the edges. Ignore them so you can kill them if you go down.
Claim your just rewards
After your victory, loot the area and grapple to the purple orb in the room.
Enter rift to exit
Consume the golden orb! You’ll receive a glide pack upgrade: Regen Delay Reduced. Before leaving, make sure to grab the two chests on either side of the purple orb rift.
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