Illhveli, Kembingur

Blood Frenzy. The kembingur has advantage on melee attack rolls against any creature that doesn't have all its hp.

Blood Scent. The kembingur can smell blood in the water within 5 miles of it. It can determine whether the blood is fresh or old and what type of creature shed the blood. In addition, the kembingur has advantage on Wisdom (Perception) and Wisdom (Survival) checks to find or track a creature that doesn't have all its hp.

Hold Breath. The kembingur can hold its breath for 1 hour.

Siege Monster. The kembingur deals double damage to objects and structures.

Multiattack. The kembingur makes one bite attack and one tail attack.

Bite. Melee Weapon Attack: +12 to hit, reach 10 ft., one target. Hit: 29 (6d6 + 8) piercing damage.

Tail. Melee Weapon Attack: +12 to hit, reach 20 ft., one target. Hit: 26 (4d8 + 8) bludgeoning damage.

Churn Water (Recharge 4-6). The kembingur thrashes violently. Each creature within 20 feet of the kembingur must make a DC 17 Dexterity saving throw, taking 36 (8d8) bludgeoning damage on a failed save, or half as much damage on a successful one. The water within 60 feet of the kembingur becomes difficult terrain for 1 minute. Each creature that starts its turn on the deck of a ship in this area must succeed on a DC 17 Dexterity saving throw or fall overboard.