He didn't kill Julius because it was unnecessary, but in just two simple strikes, he understood the strength of his Eternal Sword rule, which seemed to easily overpower and destroy Julius's Sword rule.
More importantly, in those two simple strikes, Apollo had gained a deeper understanding of his Eternal Sword Rule. Its strength was far beyond his expectations, effortlessly overwhelming Julius's Slaughter Sword Rule.
With this realisation, his confidence solidified.
He was now certain that he could easily defeat early-stage Eternal Gods with just his sword rule alone. As for middle-stage Eternal Gods, that was a different matter. The gap between each stage in the Eternal Realm was astronomical, far greater than in any previous realm.
However, he wasn't just relying on his sword.
His three additional rules—each one profound and terrifying—combined with his Eternal Sword Rule created a force that even middle-stage Eternal Gods would struggle to suppress.
