Maybe Nightwing and others would benefit from some more ideas for how to fight mages without using your own mages.
A couple of specific weaknesses of mages that spring to my mind:
- Most haven't been shown to have Superman or Flash level reaction time, so you can potentially get in an attack before they can respond
- While their shields could stop most head-on attacks, I'm not sure they'd be able to stop:
-- Someone teleporting past the shield -- e.g., port a miniature bomb right into Strange's head -- or port his head clean off his shoulders
-- Attacks that don't have to fly towards someone. E.g., when Iceman wants to freeze water, he doesn't shoot it with a freeze ray, he just wills it to freeze. So there's nothing to block. What's to stop a ruthless version of Iceman from freezing the blood in a mage's brain?
That said, the biggest flaw in those plans is you have to know where the mage is. If Dr. Strange or whoever is really being smart, he'd hide himself with invisibility or illusions until he's ready to take you out. But there are probably ways around that, too.