His first genuine battle in the Squire Realm.
His first victory in the Squire Realm.
His spar against Squire Kyrie did not even remotely count as a proper battle, that was so elementary that Kyrie had even withheld from sky-walking in combat which would have allowed her to dominate Rui with her superior experience. She held back to allow Rui to express and test himself against her and gain a better understanding of what he had and what he was missing before mopping the floor with him.
The training spars against his two Squire habilitators were even more meaningless. He had still been mastering his power back then and hadn't mastered a single technique at that point.
He felt like he had finally gotten a good grasp of what he could achieve in combat and what he couldn't. He was no longer as dominating in combat as he used to be in the Apprentice Realm. Of course, he had grown far stronger than when he was a Martial Apprentice, but his competition had grown even fiercer.