Killing his elder brother Drax, Uxas wanted Drax's birthright as inheritor of the Sight of Darkseid even more than his birthright as inheritor to the Apokoliptian throne.
The Sight of Darkseid was a ritual of ordeal for the Princes of Apokolips; surviving it as the sign of being a worthy ruler. If Drax had endured it he would become heir and his siblings all murdered in their sleep to prevent infighting.
After poisoning Drax the night before, Uxas astonished his family by arriving to the ritual in Drax's stead; several years before Uxas as the now-eldest would be eligible. Perhaps because of his youthfulness, the Sight of Darkseid had the greatest effect on Uxas over any ancestor in the thousand years of the New Gods' existence. Peering through a damaged section of the Source wall retained in the deepness of Apokolips, Uxas gazed upon the raw power of the Enigma Source and was physically transformed to have rock-like skin and eyes empty of any feeling, having been replaced by empowered hatred in the form of eyebeams connected to the angry vastness of the Omega Force beneath reality.
Uxas seeks the Anti-Life Equation, written of in dead languages from dead races on dead worlds describing the math that threads the ability to harbor Life into the universe and how it can be undone.
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Uxas here is the MU 'Executioner' Skurge with the Hiya's Injustice2 Darkseid head, boots, and armor detail grafted in place.