Nexus Guardian

Nexus Guardians were a unique variant of Vex Harpy that were encountered in the Expunge Missions featured in Season of the Splicer, serving as defenders of the Vex Network.

Expunge: Labyrinth/Corrupted Labyrinth
In the Expunge: Labyrinth mission, as well as its Corrupted variant, Elite-tier Nexus Guardian carry Data Spikes which they drop upon being killed. These Spikes can be carried to and deposited in nearby terminals, in order to disable barriers and continue progressing through the Vex Domain.

Expunge: Styx/Corrupted Styx
In the Expunge: Styx mission, as well as its Corrupted variant, Nexus Guardians appear as Major-tier enemies, whose purpose is to maintain Vex barriers that the Authentication Keys are contained in, which are crucial to disabling other gates throughout the mission.

Expunge: Delphi
The Nexus Guardians appear one last time in the Expunge: Delphi mission. Given that Delphi is a combination of all three corrupted Expunge activities, the Harpies the exact same purposes as they do in the Labyrinth and Styx.

List of appearances

 * Destiny 2
 * Season of the Splicer