Deep Into Darkness

*CONTAINS MAJOR SPOILERS FOR BOTH THE MAIN STORY AND POST GAME STORY OF FIRE EMBLEM EACHOES: SHADOWS OF VALENTIA!!! PROCEED WITH CAUTION!!!*

An AU of Fire Emblem Echoes: Shadows of Valentia.

Forneus was never able to complete his perfect creation, but did manage to send any remnant of family out before the Senate sealed Thabes away. 1000 years later, his descendant discovers the lost city Thabes and thus his ancestor's unfinished work of the perfect being that would combine the sin of nature, Thanatopheges, divine dragon blood, and a vessel. Nirnasha lays eyes upon a certain green-haired boy and makes one commitment:
"You will have the honor of being the perfect creation..."

In this AU, Marth's dad, Cornelius, is good friends with Alm's dad, Rudolf. Marth and Alm are still very young in this story and Alm wasn't sent to Ram Village until he grew for about 4 years. This story contains changes to the original story of Echoes and will contain new characters not in the game at all.

Characters will include the following:
Kian, a Rigelian scholar that has stuck alongside Rudolf and proven his worth a multitude of times. He plays a key role for the main Echoes group to grasp the situation later on in the story.
Nirnasha, Forneus's descendant that contemplates much about his family's supposedly cursed history. His undiscovered passion for his ancestor's unfinished work led him to the path of darkness depicted in the story.

For intents and purposes of this story, I'll be assuming Marth's age to be around 17-18.