Aetherbomb

Whenever a player casts a spell, put a charge counter on Aetherbomb.
Remove X charge counters from Aetherbomb and sacrifice it: Aetherbomb deals X damage to each creature and each player. If a creature would die this way, exile it instead.
"Oraduk Rai took the explosive from the artificer's hands gently, wary of the great and mystical power that lay within. And the birdsong ceased, the winds died and the heavens stilled, and the very fabric of the world seemed to shudder."
-The Saga of Oraduk Rai