From Destinypedia, the Destiny wiki
The Entangled Mind is an Axis Mind that appears in the mission, Hijacked. It's the Mind spotted by the Hidden on Nessus, and was killed by The Guardian in an effort to take and utilize its eye to find Panoptes, Infinite Mind.
The Entangled Mind will appear once entering a room in the cavern of the Tangle. It and several other Descendants will spawn. It will only appear in front of the player for a short time before teleporting out. Adds in this area aren't required to be killed. The Entangled Mind will continuously teleport out of sight until reaching an arena-like area, full of adds. The Axis Mind will stay in that area for the rest of the encounter, bombarding the player with Void blasts. It's rotating shields will also prevent of fraction of damage input. Killing the Entangled Mind ends the encounter and rewards the player with the eye capable of finding Panoptes.
List of Appearances