The Eldest Sons of the Great One and the Other, Agnar and Lucian.
Twins born at the exact same time, Lucian and Agnar were each exceptionally gifted in their respective natures; Agnar was an incredibly gifted god, with his own power almost mirroring that of the Allmother, while Lucian was a stronger spiritual god, whose inner strength was much like the Allfather.
Growing up, Lucian was tasked with leading the Ancients to preparing the Universe for the next race to come, while Agnar was tasked with expelling the corruptive power of Dark Energy back to the source of its strength; Hell. During the early years of the First Age, Lucian and Agnar jointly ruled over the Ancients, with Lucian sitting as Leader, and Agnar as High Lord.
The two brothers normally confided and counselled each other when the burdens of their Journey became apparent. For many years the bond would be strong.
As the ages dragged on and their duties became increasingly more demanding, Agnar was forced into longer periods of isolation and trying to expel the Darkness corrupting the Universe, which was starting to hinder his soul. He became increasingly resentful of his duty, and jealous of the Great One's favouritism to his twin. While Lucian assured Agnar that their creator did care about him, the High Lord did not see it. Still, he maintained his faith and loyalty to his brother.
However...not all things would remain the same between them for long.