The Scourge of the Sea

Flying, Haste, Menace, Lifelink
{t} Add {7} to your mana pool
{t}{u/b}{u/b} add +5/+5 until end of turn
{t}{4} Reveal The Scourge of the Sea. put a prey counter on every creature and Planeswalker target opponent controls
When The Scourge of the Sea enters the battlefield untap all creature and land cards. Destroy all creatures and Planeswalkers with prey counters