Rukelion didn't want to fight people who were only defending themselves on the behalf of his worst enemy. He had no doubt that Mirea had started the conflict that led to the crown prince heading toward Zel in the first place.
Even if they didn't, he didn't want to be complicit in destroying an innocent nation for someone as despicable as the Mirean king. Yet he found himself unwillingly on the battlefield.
He purposely didn't kill anyone since he was still trying to make diplomatic relations work out somehow. All he did was dart around the battlefield protecting the precious few people who were involved in his treasonous plan. He did this for over a week and was certain the Zelish soldiers had noticed.
Gaining their goodwill was paramount. He needed to do that before he tried bringing them over to his side.
