And he didn’t just destroy Earth or Reshlan or Vocado with them on it when he could have.
Banespell is about being tactical. He tried to minimize damage done with maximum return.
He just finds it interesting that the ‘good guys’ have repeatedly nearly blown up planets and slaughtered billions.
Kind of proves his point in his mind, that Inanna is too reckless and leads others to act in a similar manner.
That’s how he sees it, at least.