How about that? you just grab feathers, fly and zerg?
I've been running with my normal spec/glyphs, with Glyph of Conflag changed to Glyph of Siphon Life. Sacrificing my Voidwalker.
Soulstone yourself before pull, run up and make the Firelord near Rhyo run away then just die and rez to clear the little adds. Then when she does her tornados, stack Immolate to it's max duration and fly over there. You get a nasty DoT for being out of bounds but you can heal through it with practice.
Aim to have 4 embers stacked for the tornado phase, then start with Shadow Bulwark (Voidwalker ability), and Ember Tapping 2-3 times as needed. When the damage starts getting higher, pop Unending Resolve, Dark Regen and Glyphed Healthstone. Then Dark Bargain at the end if needed, which I haven't been needing the last 2 weeks. If it gets messy you can also Death Coil one of the nearby critters, and use the last Ember Tap as well.
Haven't been able to kill her in one lap yet hence why that is necessary.