Crimson Desert: A Shadow in the Void

Game8 files this under chapter 12, The Abyss, as a main sub-quest. You enter through the gate at the Crescent Skybridge, solve the gate puzzles, and reach Crow's Nest and the Dimensional Bonds. Caliburn is there, and the fight is three phases. Both the quest card and the chapter list agree there is no item reward at the end.

The title shows up in several languages in search logs. I am keeping the English quest name from the guide and not translating the steps into a second walkthrough. If you are still in chapter 11, Strange Manor is the earlier manor job, not this void fight.