Sunderflock

This spell costs {X} less to cast, where X is the greatest mana value among Elementals you control. Flying When this creature enters, if you cast it, return all non-Elemental creatures to their owners' hands.

From Magic: The Gathering.

Open the interactive version on https://mythscribe.cloud/app/tcg/cards/cms6oje33e0b1pb1hboa1c63y.