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The Contaminator Heavy is a Maliwan trooper found in Borderlands 3. They are a corrosive variant of the Heavy Gunner.

Contaminator Heavies also spawn during the Bloody Harvest Halloween event when inside The Heck Hole. Although functionally the same, they are renamed "Pathologist Heavy".



Contaminator Heavies are equipped with dual-fire caustic spray nozzles. These weapons are capable of firing a spray of acidic ooze that can be used in a variety of ways to damage and kill their targets. While offensively focused, the jets of acid can also be used in conjunction with a jump to launch themselves across the battlefield and reach their targets.

A Contaminator Heavy has several options for attacks. They can fire bursts of caustic ooze forward, arc a larger ball of acid into the air which can then explode into small bursts and cover a large area, or fire a jet of the acid when a target is in close range. Like all enemies, they will also use melee attacks when their target is too close. A Contaminator Heavy is resistant to corrosive weapons and are are not armored (therefore are not heavily damaged by corrosive attacks).

The glass bulb on a Contaminator Heavy's back is his weak point. Similar to the vast majority of Maliwan Heavies, concentrated fire on this backpack will cause small jets of acid to spray until the case breaks. This instantly kills the Contaminator Heavy and causes an explosion that leaves a puddle of caustic ooze on the ground for some time.

While all Maliwan Heavies can be dangerous, most characters do not take more damage from corrosive than other elements, however, the corrosive caustic acid of the Contaminator Heavy can pose a significant threat to Moze's Iron Bear. It is best for Moze to utilize basic firing methods, or for Iron Bear to quickly focus its weaponry on the Contaminator Heavy.

Amara's action skill can also prove an obstacle to itself when facing a Contaminator Heavy and should be simply swapped out for another element during a fight. While a Contaminator Heavy will still take damage from the strike, the corrosive status effect applied will be resisted.


  • There exists a dark variant of the Contaminator Heavy that can be found serving General Traunt on Nekrotafeyo or on the Slaughterstar 3000. Aside from their name and color scheme, they are functionally the same as their basic counterparts.
    • There also exists a Special Ops variant of the Contaminator Heavy found at the Maliwan Blacksite at Midnight's Cairn, where they serve as guardsmen for the weapons project Valhalla. Aside from the name and color scheme, the Heavy retains their tactics.
  • In Mayhem Mode and True Vault Hunter Mode, they are renamed Corroder Heavyweight.