's soul may be defeated, but his armies remain. See to their extermination.
― Eris Morn
The Extermination was a quest given by Eris Morn after completing the Rise of Crota quest in The Dark Below. This quest unlocked the Will of Crota strike and, depending on a Guardian's class, awards Mark of the Duskborn (Titan), Cloak of the Dusktorn (Hunter), or "Curse of the Hidden" (Warlock). It was made unavailable in The Taken King.
- Defeat 25 Hive Knights and Wizards, then bring proof of their demise to Eris.
- In Patrol, defeat the Heart of Crota in the Refinery, Hand of Crota in the Lunar Complex, and Eyes of Crota in the Terrestrial Complex.
- Hunt and kill Omnigul in the Will of Crota strike.