The Green Shell is an item in Super Mario Galaxy, Mario Kart: Double Dash!!, Mario Kart 64, Mario Kart Wii, and Super Smash Bros. Brawl. They are Koopa Shells with no Koopas hiding in them. In Mario games such as New Super Mario Bros. Wii or Super Smash Bros. Brawl, Koopas go in they're Green Shells when stepped on. You could grab them and throw them as they will roll across floors, defeating or Koing (Brawl only) others. In Mario Kart: Double Dash!! and Mario Kart Wii Green Shells were common items. Like Bananas, they appear frequently once you are in 1st or 2nd place. When thrown, unlike Red Shells, they move across the course. If they hit an obstacle they go the opposite direction. It is quite rare to get a Green Shell to hit an opponent in these games unless, you throw them when you are close behind an opponent (let's say about to hit the kart's bumper). If Green Shells do hit opponents they break. They also break after hitting obstacles too many times. Green Shells are shells you must keep an eye on even in Super Smash Bros. Brawl. In the Mario Karts, if you are not careful your Green Shell could hit you! In Brawl, Green Shells could be stopped by simply jumping on them. Opponents will pick these up and throw them at you. They have high knockback and KO power. If your Damage Ratio is at 2.0 a thrown Green Shell can instantly KO you like a Bumper will.