Dark Age: Mage
A water spirit from Russian or slavic lore. The males resemble old men with webbed fingers and toes. They use humans as slaves in their underwater domains.
Brodir noticed that in using his magic to escape a grapple from Norgo that his magic was met with some resistance. This may mean that the Vodyanoy have some magical bonuses to their grappling.
Norgo also required the exchange of three foreign items for the return of the three guards he took from the party. This may be an indication that spirits who are tied to a certain location value items from afar – possibly as a mark of status.