So, the story goes like, a son of Hadum that resented and defected his own race or faction and was ripped off from his title as a part of Hadum's army. Losing his prowess and was exiled into nothingness and found his way to the Elion realm.

A class that uses a scythe and summons his loyal shadow army from Hadum as an awakening. Maybe a Shadow Monarch? (A fan of Solo leveling)

And a class that uses a dagger that floats and can cut through the void as a succession. Can be named as Umbra?

I mean he might sound OP since he's titled as exiled son of Hadum but we also have Archer and Fletcher which is the forgotten son of Silvia.

Speaking of Archer and Fletcher as the forgotten son of Sylvia, I think PA really did forget about these classes. I can hardly find Fletcher these days and only few Archers. Maybe it's their lack in mobility during Black Sun. And by mobility, it means a skill that covers great distance with short cool down. I mean Archer/Fletcher is a champion of Sylvia a goddess, and is on the bottom rank of class tier lists sounds sad.