Complete tiers of the Nightmare Containment public event within the Derelict Leviathan and bind your Vestiges of Dread at the Nightmare Harvester after completing the final tier to create a Bound Presence.
Each additional time you bind after completing the final tier has a chance to reward a Bound Presence.
Flavor text
In order to perform a ritual to sever Calus's connection to the lunar Pyramid, Eris has sent you on a mission to harvest the essence of Nightmares on the Leviathan and beyond. Destroy these creatures and contain their power for her spell.