Leviathan of the Deep Dark

Trample, menace
Whenever your opponent draws their 2nd card
during each of their turns, you may reveal this
card from your hand and pay {2}{u}{b}{u/b}. If you
do, until end of turn, you may cast this card as if
it had flash without paying it's mana cost.
"My first experience with this beast was nothing
less than terrifying."
- Admiral Brickell, Captain of the Seas