It wasn't actually the most reliable way to defeat an elder god in his spiritual form, but Isis quickly came up with one. When Hades flew to attack her again, Isis bombarded him with special arrows. Hades frowned since they didn't have any divinity and the mana on them was also low, so he decided to just let them hit him. However, he regretted that a little when the arrows touched and stole his mana. It stole a minimal amount of mana, but Hades could see what Isis was planning.
"That is a useless effort," Hades said.
"I don't think that any effort is useless," Isis said.