Gutsoul, Heat of the Deep

{3}{u}: Target Kraken, Leviathan, Octopus, or
Serpent can't be blocked this turn.
Whenever a Kraken, Leviathan, Octopus, or
Serpent deals combat damage to an opponent,
look at that players hand. You choose a nonland
card from it and exile it under Gutsoul, Heat of
the Deep. You may look at and cast that card for
as long as it remains exiled, and may spend mana
as though it were mana of any type to cast that
spell.