It's nice to have a villain with a brain. It's a very rare thing in cultivation series. That being said, although I know why he's killing off everyone stronger than him, I'm not sure if that's the best course of action. Maybe send someone out to the Azure Feather family to warn XingHe about the elder. Then let XingHe handle the problem. It would work out either way for him. If XingHe wins he owes you for the warning. If the Patriarch wins you just have to deal with him afterwards. Let them both expend their energy and swoop in after the fact to clean up the mess.