Essence Thief is a medium armor set. When you deal damage with a Light Attack, you draw essence from the enemy. Collecting the essence heals you 3900 Health, restores 3900 Stamina, and increases your damage by 10% for 10 seconds. Essence lasts 5 seconds, and spawns close to your target.
The Essence Thief set is part of the Imperial City DLC. It drops in White-Gold Tower in the Imperial City. Each set item is bound on pickup. You can acquire medium armor, weapons and jewelry of this set in the Xivkyn motif style.