> She is Immortal, not biologically, but she can not die.

Then spread out her essence so far it'd take her centuries to piece herself together again to even think. Makes no difference- Iscandarians and Equestrians rely on her for power. If she's absent, their magic loses its power, even if only partially. A shield that would stand for days would only stand for hours, a weapon that would burn through a ship would simply damage the armor. 

She is the source; the generator. Her alignment affects her underlings. If she is scattered, their minds would be torn, weakened, maybe even broken.