Mr. MistMeister
Ari and Caper run across Mr. MistMeister, a dangerous water elemental, on a hike outside of Caper's Shire. Before he was Mr. MistMeister he was a water sprite. One day when he was flying a potion maker, greatly afraid, threw a potion of gaseous form on the sprite. The combination of magicks locked the elemental into it's gaseous form and Mr. MistMeister was born.
He used to enjoy coralling loads of fish into fishermen's nets so they became so heavily laden that they would break or even capsize the fishing boat. In his mist form he has been corraling people by showing them abandoned houses from the past and luring them into his misty form.
He is not evil. He just does what he does because he doesn't know what else to do. He could be convinced to take up another avocation but he can only be destroyed with very high level magic that counters both the potion and fey magic at the same time.
Pictured is Dancing Fairies painted in 1866 by the Swedish painter August Malmström. Unlike the faires pictured Mr. MistMeister cannot return to the water but is locked above ground as a mist.