Fe Main lord concept (Fe 7 side story)

(This is for my AAA contract character creation project for year 2 of collage) The new game I am imagining will coincide with the events of FE7 She is a morph created by Nergal, like Sonia and Limstella, but she broke free from Nergal and want on her own journey to get stronger and eventually kill him, she has access to magic and spear.