Nihook, Tamer of Titans

Ward, {2}
Whenever a Leviathan, Kraken, Octopus, Turtle, Whale, or Serpent enters the battlefield, draw a
card.
{2}, Target Leviathan, Kraken, Octopus, Turtle,
Whale, or Serpent becomes a Mount in addition
to its other types with "Rider gets all of this
creature's abilities, +X/+X where X is this
creature's power, and Mount {3}."