Oculyst

The Oculyst is a mysterious floating drone with a translucent blue body that can randomly appear in missions when a player has a mastery rank of 3 or above. In the event that the player is not noticed by said enemies when they appear, they can be seen scanning random objects that are in a close vicinity to them. From the information currently available it can be assumed that the Oculysts are Sentient drones. Scanning an Oculyst for the first time triggers the Natah quest.

Tactics

 * The Oculyst will only spawn if at least one of the squad members is of Mastery Rank 3 or higher; it will announce its presence with a continuous, distinct howl. Their sole interest seems to be scanning objects such as containers and dead bodies.
 * After completing several scans, they will eventually lose interest with the site and vanish.
 * This unit is impervious to damage and thus cannot be killed. It can be scanned though, which will prompt the Oculyst itself to scan the player. If this is achieved, it will leave the site.