Slime Ghost

Slime Ghosts are slimy, green, glowing entities of unknown origin that can be found in Flatbush. They are capable of speaking, spreading, and taking control of people's bodies. Fortunately, they can be defeated with proton packs, such as the ones used by the Slime Busters.

History
Slime Ghosts were only ever seen in The Super Mario Bros. Super Show! live-action segment "Slime Busters". Several Slime Ghosts had invaded Mario Brothers Plumbing at some point, and were giving Mario and Luigi more trouble than they could handle. As one Slime Ghost in particular pulled Luigi into the back room, Ernie Hudson of the Slime Busters showed up and went on a quest to hunt any Slime Ghosts he could find. Ernie eventually found one in Luigi, who had, unknown to them, been possessed by one while he was in the back room.

While Ernie and Mario searched around for traces of Slime Ghosts, Luigi took a bite out of his plate, followed by part of his body turning into slime. With no other choice, Ernie was forced to shoot Luigi, and was held with the risk of tuning him into a drooling, moronic zombie if something went wrong. Although Luigi tried to deflect Ernie's proton shot with a pizza pan, Ernie succeeded in ridding him of the Slime Ghost. However, the now-dented pizza pan was possessed by the Slime Ghost, and asked for Ernie to take him away from Mario and Luigi, whom he referred to as "Goombas".

Trivia

 * Slime Ghosts are based on the character of Slimer from the Ghostbusters series.