Savouring the sensation of killing High Millinar Julas was entirely what he wanted, not needed.
But making sure that he died was something needed.
Rex wasn't dumb.
Dragging out the kill so that he could savour the death of his enemies who dared cross him would be risky, as the other enemies might be able to rescue them, saving them from death's mouth. So—he made sure that it wasn't possible.
Just like what he did to High Millinar Vlaos and Angela, he used the Divine Tainting skill.
Achieving victory within the Purgation Duel would win over High Lord Rashal for good and also save him from future enemies—but it also served as a hunting ground for him. It was a perfect place for him to increase his divinity points.
Naturally, he made sure he killed his enemies through the Divine Tainting skill.
Before he tried ending High Millinar Julas, he had already planted the Heresy Mark.
