The Sky Burners are the "celestial demolitions" fleet of the Cabal. The Sky Burners were ordered by the Emperor himself to board the Dreadnaught and kill Oryx, by any means necessary. They crashed their warship into the Dreadnaught's hull, and are fighting a protracted war of attrition deep behind enemy lines. They can be identified by their light blue armor and brush on their helmets.

To start the quest you need to obtain Skyburners Command Beacon which may drop from Cabal Centurion and Colossus on The Dreadnaught.
Use the beacon to activate the console which is located in Dreadnaught in the Cabal ship left from the entrance. A dropship will come with a Cabal Champion. Defeat the champion and he will drop Skyburners Deployment Codes.
Use Skyburners Deployment Codes to activate the console located in Mausoleum. You will receive a chain of missions. Complete missions within the time limit. Once last mission is complete you will get the Skyburners Security Pass.
Use Security Pass in the same room in Mausoleum to activate the door that requires this pass. Skyburners chest is behind this door.
Loot: Vanguard reputation, Crota's Bane reputation, Calcified Fragment, engram, Glimmer.

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