Spiny Shell (blue)

The Spiny Shell is an item from the Mario Kart series, making its first appearance in Mario Kart 64 (in which it was previously named Blue Shell). The general purpose is to knock out the 1st place driver of the race when the player uses it, although that's not always the case, as it would sometimes hit the one in 2nd place. Blue Shells cannot be avoided without cheating, but a good strategy when about to be hit by one is for the player to stop on the track and hope opponents come up behind them and get blasted by the shell as well.

In Mario Kart 64 and Mario Kart Super Circuit, the Spiny Shell tended to slide along the track, knocking over other karts that happened to be on its path, to finally knock over the first place kart. Sometimes, walls and other obstacles caused the shell to flip over and fall off of the screen. In these two games, the Spiny Shell had a distinctive siren, but it was later changed to a whoosh.

In Mario Kart: Double Dash! for the Nintendo GameCube, the Spiny Shell gained a pair of wings, which is its present appearance. Upon being shot, the Spiny Shell goes flying at very fast speed to the header racer. Once locked on its target, the shell hovers briefly above the kart and explodes, causing the kart to fly, as well as destroying the items held by the racer. Other drivers that cross the impact zone would be blown up as well in the explosion or spun around.

The Spiny Shell has later appeared in the Nintendo DS game Mario Kart DS, and the Wii game Mario Kart Wii, as well as in certain Mario sport games.