Konenmaru

Konenmaru (こねん丸, Konenmaru) was Suiens' summoning animal that had met his fate at the hands of Kakashi's Raikiri in the Naruto: Mission: Protect The Waterfall Village (novel). Before he could kill Suiens' three amegakure teammates.

Appearance
Konenmaru had the appearance of a black catfish.

Nature Transformation
The giant catfish had the great ability to use water release. Even when battling it's opponents, and even turning on it's comrades.

Trivia
Konenmaru in it's Japanese kanji (こねん丸), means "The concentration of thought round".