Blood Frenzy. The giant shark skeleton has advantage on melee attack rolls against any creature that doesn't have all its hit points.
Bite. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit:22 (3d10 + 6) piercing damage.
A giant shark is 30 feet long and normally found in deep oceans. Utterly fearless, it preys on anything that crosses its path, including whales and ships.