This was my entry for the second round of the So You Want To Be An OSR Superstar competition. It didn't make the cut, so I thought I'd share it with my readers. Congrats to the winners, and I can't wait to see who wins round three!
Nanaue (Lycanthrope, Wereshark)
Hit Dice: 6
Armor Class: 5 
Attacks: 2 claws (1d4), 1 bite (2d8)
Saving Throw: 11
Special: Lycanthropy, hit only by magic or silver weapons; breathe water
Move: 9 / 18 swimming
Alignment: Neutral, though Chaotic when frenzying
Challenge Level/XP: 8/800
Nanaue are half-man, half-shark lycanthropes who are part of a royal bloodline. All original, pure-blood nanaue are descendants of an ancient, legendary “Shark King” who ruled both the sea and the coast many generations ago. Most nanaue who live today also hold positions of royalty in coastal villages and towns, due to both their natural leadership abilities as well as in honor of the Shark King, the first nanaue. However, once every month, their bestial nature overcomes them, and they must return to the oceans for 24 hours to unleash their alter-ego.
In their shark-form, nanaue appear as a 7-foot-tall, blue-skinned humanoid with a large shark’s head and a pair of webbed claws and feet. With these webbed appendages, the nanaue can swim at an incredible rate of speed. Once in the water, the nanaue will attack and consume nearly any prey it encounters in a chaotic feeding frenzy. Once a nanaue deals damage to any “prey” and catches the scent and smell of blood, it will continue to attack and pursue its victim until either one of them is dead. The nanaue will even pursue its victim onto dry land to finish him off. Although the lycanthropic curse of the nanaue can be spread by its bite, few victims survive the savage feeding frenzy that occurs once the nanaue smells and tastes blood.
It’s said that the nanaue may be unaware of its dual nature, leaving the palace walls in a dazed trace only to return 24 hours later exhausted and full with no memory of what transpired. If some of the local fishermen claim to have seen a monster in the nearby waters, the local chieftain may ask for assistance in dealing with this aquatic threat, not realizing that the “monster” is actually himself in his mindless bestial form.
The ConManKen Video Has Been Found - Watch and Listen at Your Own Risk - #ConManKen doesn't stop fleecing his marks, he just has a new community of marks. *Previous post here*.