Big Fish

Big Fish (ビッグフィッシュ) is a big robot fish enemy that was originally used for crime prevention, jumping out of ponds to scare criminals. Big Fishes appear suddenly from the pits of the third Wily Castle stage to attack Mega Man 2, causing heavy damage. It also appears in the stage of Mega Water. S and the fourth Wily Tower stage in Mega Man: The Wily Wars.

In the original NES version of Mega Man 2, the Big Fish is invulnerable to all Special Weapons but the Quick Boomerang and Crash Bomber; this was apparently a mistake, since in the Mega Man: The Wily Wars remake, it is invulnerable to all weapons, including the ones from Mega Man and Mega Man 3.

Hits Data Chart
Amount of shots/hits from Special Weapons it takes to destroy a Big Fish.

Trivia

 * In the Mega Man cartoon show episode titled "20,000 leaks Under The Sea", Dr. Wily launches a fleet of "Cudabots" that look like a smaller version of the Big Fish.