From Destinypedia, the Destiny wiki
Vex (formerly) Taken
Void Aeon Maul
Summon Taken High Durability Rapid Movement Rotating Shields Midair Levitation
Erosus, Spawn of Quria, once Erosus, Imprisoned, was a Hydra who was one of the few Vex to be Taken during the Calculated Action Quest. Before it was able to work towards Ir Arok, Tongue of Quria's objective, it was neutralized by The Guardian.