Even if he was boar-headed, Emodao decided not to be boar-headed today. He had already released his anger on those punks from the Human Divinity Army earlier because they were nothing to him. As for a lieutenant general like Severed Glacier, he would need more than this piece of meat suit and a few moves from that pill.
However, he did have Xu Rouguang, right?
Well, even if Emodao knew that Xu Rouguang would do well by learning on the battlefield, he didn't want Xu Rouguang to believe that he could utterly become a god one day. Because he was the type that would be desperate for power just to protect the ones he cared about. Emodao was just a demon king to Xu Rouguang, and demon kings could be easily crushed by gods and even the Sacred Guardians.