The Monster Cards published by TSR back in '82 seemed to be an idea way ahead of its time. A few minor changes to the format, like making them standard poker sized so they could fit card protector sheets and be organized in 3-ring binders, could have made them a real hit. As it is now they are fairly rare. I have a pretty good set of them, but since there is no numbering system on them it is hard to tell how complete the collection is.
You don't see enough art by Darlene from those days, so here is her Sea Wolf illustration for your viewing enjoyment.
LYCANTHROPE, SEA WOLFFQ: Very rare
AC: 6 (7)
MV: 30"/ /12"
AL: Neutral evil
SZ: M (6'-7')
AT: 1 (3)
DM: 2d4 (1-2/ 1-2/1-4)
L/XP: II/50 + 3/hp
These savage lycanthropes have two forms. The first form is a furred mammal, porpoise-like in shape, with a wolf's head. In this form, sea wolf packs hunt the creatures of the sea, surrounding their prey and biting with their canine fangs. The second form is a wolf man, a man shape possessing the fur, claws, and teeth of a seawolf. (Statistics for the wolfman form are given in parentheses above.) Seawolves breathe air, and must surface periodically.
Unlike other lycanthropes, seawolves can be hit by normal weapons. Humans taking 50% or more damage from sea wolves will contract this form of lycanthropy. If humans are infected while on land, they will travel as fast as possible to the sea. At sea, they will disappear overboard on the next full moon.
If a sea wolf pack encounters a ship, the sea wolves will change to wolfman form and attempt to board it. Their only purpose is to slay all those aboard and sink the ship.