User blog comment:Godzillavkk/Kingdom of the North vs Northern Water Tribe/@comment-11361577-20190522211744/@comment-4708902-20190523002154

He probably doesn't need to. If he can warg the moon, he'll have all it's power, and could shut down waterbending. And since the spirits are phsyical beings, and thus can be killed,I think warging will work on them.