Cosmic Prophecy

Place this card face down.
When opponent/s casts a spell,
summons a creature or
planeswalker within 5 turns,
opponent/s creatures and
planeswalkers are tapped for 5 turns.
If no opponent casts a spell,
summons a creature or planeswalker
within 5 turns, destroy Cosmic Prophecy and
3 cards on the battlefield that you control.