Battle Salmon

Battle Salmon are mechanical fish in the Smithsnorian Museum of Wario: Master of Disguise. They appear in an underwater part of the museum. They are thin fish that to do damage by colliding into Wario and destroying themselves.

In-game description
''A paper-thin fish that moves with the speed of 10,000 winds and sacrifices its own life to damage enemies. ...What a jerk.''