Servant of the Heart
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The Servant Acolyte can be spotted kneeling at the site of a downed Seeder Ship, after going straight from the entrance and forking left after a flight of steps. Killing him will summon the Heart of Crota in addition to mobs of Thralls and Acolytes. The mobs will keep spawning until the Heart is killed. Being killed will reset the process, and the original Servant of the Heart will not reappear, forcing a reentry.
List of appearances