NHF – new heroes for Heroes V 3.1.

The special ability is too strong. It's game over for everyone.

Added 1 minute ago
And it's unlikely that anything can be done about the Necromancy.

You could give her the Necromancer's amulet instead, if that's not possible. And increase all stats by 2, for example.
I wouldn't say that the special ability is too strong. 10% Necromancy and -3 (3.5) to morale and luck at level 20 is not that much...