I know, hear my thoughts: The Fallen created a Servitor to [i]mimic[/i] the Traveler's power (because all Servitors are already made in its image, y'know?). It's huge, insanely powerful, and a threat. Taox is not a Hive, but is still a Mother: that's like a primitive Wizard. She's still an ancient and powerful foe, who is being chased by the sisters of Oryx, more insanely powerful foes. Way I see it, she doesn't need to specifically be a Hive.