He was once a maggot in the slag field, who killed his father and became a demon, tempering fire into a blade, just to tear this man-eating old world apart.
He sat on the throne of the evil god, thinking that power could bring order, but what he got in exchange was fear and betrayal from all living beings.
When everything he protected collapsed again, he finally understood:
The future of all living beings must be paved with the bones of "gods".
Therefore, he chose to become the overthrown giant tower - using his own complete fall to exchange for the first glimmer of light for the new life outside the wall.
This is a war in which the darkest past is exchanged for the dawn of the future.