Gargantuan Leviathan

Predatory Strike Whenever Gargantuan Leviathan attacks, target defending player must block this turn, if able.

Other deep sea creatures you control have intimidate.
At the beginning of your upkeep, if you control 5 or more deep sea creatures, deep sea creatures gain trample and menace. (Deep sea creatures are leviathans, krakens, octopuses, and serpents.)

Shroud.