Amatsu, Looming Calamity

Flying

Whenever you cast an instant or sorcery spell, put a +1/+1 counter on Amatsu, Looming Calamity.

Heaven's Catastrophe — {3}{u}{r}{w}, remove X +1/+1 counters: Each opponent may pay {x} mana. For each opponent that does, they return all creatures they control to their hands. For each opponent that doesn't, Amatsu deals twice X damage to them and each of their creatures. Creatures that would die this way are exiled instead.