Combo Breaker

You may only cast Combo Breaker if another
player has cast 3 or more spells this turn.
Combo Breaker can't be countered.
End the current turn. (Exile all spells and abilities
on the stack, including this card. The player whose
turn this is discards down to their maximum hand
size. Damage wears off, and "This turn" and "until
end of turn" effects end.)