Eye of Riven

Eye of Riven (plural Eyes of Riven) is an elite Taken Captain that appears only in Last Wish. Killing one drops Taken Essence.

Eyes spawn during the Morgeth fight, usually one on each side of the arena. Taken Essence can free a player locked by Umbral Enervation: a player with no Taken Strength kills an Eye, picks up its Essence and uses the grenade ability on the trapped player, which transfers that player's Taken Strength. Reported cleanse windows range from 15 to 20 seconds.