As he is a Hypno Mantis he will lob sleep pods upon the player, then slash at him with his claws. Along with that, he possesses a Persistance Aura, meaning every enemy around him will be resurrected once. Which is even upon the fact, that Yegg is accompanied a big bunch of mobs. That includes Hypno Mantises. The best way to deal with Yegg would be to, kind of, create a lake of blood, that is destroy all mobs ASAP and aim for crits, as lethal crits get around the Persistence. Heroes with Flame Surge, as well as Skar in their squad (or Lumin Gamma with Blitz in his squad, during Overdrive), would be excellent, since they can do critical hits almost all over the area, considering how big the area Flame Surge covers is.
Another thing to do is to hunt down Yegg if possible, before all the other enemies come. (Unless overwhelmed by amount)
- Yegg is a reference to MaxisYegg, Paul Sottosanti's EA username. MaxisYegg is well know for having announced many Darkspore heroes upon request on the forums, as well as answering many questions.