The Professor sends the team to rescue a beached Livyatan, a massive carnivorous whale. As they attempt to drag it back to sea, Trina attacks with her Mosa-Marine. The Ptera-Wing and Stego-Sub combine to form the Stego-wing to fight back, despite being unfit for underwater battles. The Mosa-Marine gains the upper hand, but help from the rescued whale might just save the day-and Dinoster!