Electro-Koopa

Electro-Koopas are Koopas in Super Mario Sunshine with blue shells on their back that are electric and walk on all fours. They mostly appear in Pinna Park and also appear in the King Boo fight.

To attack they will throw their shells at Mario so Mario has to avoid it, or he'll get Electrified. The shell will fly back onto them like a boomerang. To defeat them, spray water on their bodies to distract them just before their shell comes back so that they get electrified or simply stomp on it. If an Electro-Koopa throws its shell over a cliff so that it cannot return, the shell will disappear after a few moments, and the Electro-Koopa will spontaneously grow a new one. Similarly, the shell will be destroyed if it lands in water, though it still takes some time before the Electro-Koopa replaces it.

There are also red versions of the Electro-Koopa. They appear in Pinna Park and Pianta Village where they climb on metal screens. To defeat them, Mario should kick, punch, or Ground Pound them from the other side of the screen. When this happens, they fly off into oblivion. They will shock Mario if he comes in contact with them.

There is also a green breed that resembles a giant (red version of) Electro-Koopa. It slept atop the ferris wheel in Pinna Park where electrical discharge from its shell made the ride spin extremely fast. Mario had to defeat the Electro-Koopa by flipping the grate beneath its belly; it'll then fall in the water, causing a Shine Sprite to appear and allowing the ferris wheel to returns to normal speed. It might be a leader among the Electro-Koopas.

Trivia

 * A shell-less Electro-Koopa appears in the board game Nintendo Monopoly.