Leviantha, Terror of the Seas

When Leviantha, Terror of the Seas enters the battlefield, if you cast it, return all creatures and planeswalkers your opponents control to its owner's hand.
When another Leviathan, Serpent, Kraken, or Octopus enters the battlefield under your control, you may draw a card and tap a target creature that your opponent controls.
Tap three other untapped blue creatures you control: Leviantha cannot be blocked this turn and gains Hexproof until end of turn.