History of Controlled Burn

Controlled Burn is a Season of the Haunted triumph toward the Reaper seal: on the Derelict Leviathan, defeat each roaming Nightmare target in the Pleasure Gardens.

How to complete

1. Load into the Derelict Leviathan and go to the Pleasure Gardens.
2. Hunt the two roaming named Nightmares: Tlazat, Fed to Beasts (a Cabal Psion, seen toward the top-left) and Uoac, Spine Breaker (a Colossus, toward the top-right). Spelling of the names and exact spots vary between guides.
3. Defeat both. They can take a while to spawn, so wander the zone until each appears.

Seal

Completing it counts toward the Reaper seal (one of the Shadow's Return steps, per the guides). Season of the Haunted content has been vaulted; check current availability.