Spiny Shell (blue)

The Spiny Shell (also called Blue Shell) is an item from the Mario Kart series. It first appeared in Mario Kart 64, where it was known as the Blue Spiny Shell. Although many people call this item the Blue Shell, it is different from an ordinary Blue Shell by having spikes and sometimes wings.

The Spiny Shell has appeared in many Mario Kart games, being an obtainable object by taking an Item Box. Its general purpose is similar to that of a Red Shell, except for that it targets the player in 1st place. Of course, its function may vary slightly regarding to the game where it appears. Aside the Mario Kart games, the Spiny Shell is a power-up in some Mario sport games.

Mario Kart 64
The Spiny Shell is first introduced in Mario Kart 64. In the game, the shell had various spines over it and traveled along the ground. It was essentially a blue version of the common Spiny Shell and named here Blue Spiny Shell. Any player outside of first place could receive this item, although there were certain Item Boxes along the way that automatically gave players a Blue Spiny Shell, regardless of their position.

When a player used a Blue Spiny Shell in Mario Kart 64, it traveled along the ground and struck any player ahead of the player that used the item. The only way to avoid an oncoming Spiny Shell was to veer out of its way at the last second, where it could miss its target and keep on going. The first place person cannot avoid the Blue Spiny Shell unless he/she happened to have a Star or Boo on hand or if he/she simply plummeted off the course to avoid the shell. When the Blue Spiny Shell hit the first place person, it would flip and fall off the screen. If the first place person did manage to avoid the attack by plummeting off the course, the Blue Spiny Shell could actually circle all the way around the course again to attack the first place person. This would also happen if the player uses Boo.

The player could also drag a Spiny Shell behind the Kart while holding the button without releasing it. The shell could then absorb any attack from behind and hit incoming players, and remain indefinitely active throughout the race, though if the player was attacked by a Star or fell off the course, the item was lost. If the player is in first place and releases the item, the shell will instantly return and hit the player. Unlike the other shells used in the game, a Spiny Shell made a siren sound as it came close to a Kart.

This item is indestructible against most items, but it can destroy itself whenever it hits the leading racer or a wall. It also can't pass through certain obstacles, such as large gaps.

It should be noted that in Luigi Raceway, there is a Luigi Balloon that will dip down with an item box on the bottom. If players get that item box, they will always get a Spiny Shell.

Mario Kart: Super Circuit
The item served the same function in Mario Kart: Super Circuit for the Game Boy Advance, although the shell had a darker blue color. When shot, it made a distinct siren sound to alert those ahead that the shell was coming. Like the Red Shells in the game, it can be dropped behind the player and will activate only if the kart in the first position passes directly by it.

Mario Kart: Double Dash!!
In Mario Kart: Double Dash!!, The Spiny Shell was changed significantly. It is a standard item that any player could obtain by running over an Item Box or even a Double Item Box. From this game, the Shell appears with a pair of wings that allows the item to fly instead of sliding over the ground, which allows it to skip any obstacle found in the course.

The item is only given to the racers that are in fourth place or lower. When thrown, the shell flies at incredible speed to the current head racer, bypassing all of the other positions. After finding its target, the shell hovers behind the vehicle to home in on it and explodes on contact. The impact causes a blue blast (similar to a blast from a bob-omb) and throw the player up into the air. Other racers near to the leader would also be blown up by the blast or spun around a bit after the impact. The blast will also cause all the items held by the player to drop to the road.

The Spiny Shell always goes for the leading player in the race. Therefore, if the player in first already crossed the finish line, any Spiny Shell shot after that point will go to the active leader of the race (in this case the second place racer). Thus, once the player in second crosses the finish, the shell will target the player in third, and so on and so forth. Additionally, once a player holds a Spiny Shell, other racers cannot receive another shell until the player has used it and the item has exploded over its target. This rule is kept for later Mario Kart games.

Unlike the land variation of the Spiny Shell, this shell can bypass large gaps. It also doesn't damage any racers until it explodes.

Mario Kart DS
In Mario Kart DS, the Spiny Shell hasn't changed since its redesign in Mario Kart: Double Dash!!. The Spiny Shell worked in the same manner as in Mario Kart: Double Dash!!. It is obtainable for fourth to seventh place. Once fired, a Spiny Shell flies following the road to reach to the header racer. Once locating its target, the shell flies around briefly over its target and falls over the vehicle, creating an explosion to send the vehicle flying and destroy the items held by the racer. Almost unavoidable, a player can avoid the explosion by using items like a Star, a Bullet Bill, or Boo. For unknown reasons, being hit by certain items, such as a Red Shell or a Fake Item Box will also prevent the player from being damaged by the explosion.

The item is not available in Battle Mode.

Mario Kart Wii
The Spiny Shell made its latest appearance in Mario Kart Wii for the Wii. Its function is identical to Mario Kart: Double Dash!! and Mario Kart DS, and can be obtained if the racer is in third place or lower.

The item is far more common in this game, especially if the options are changed prior to playing the Versus Mode. If the option is changed to "Frantic," then Spiny Shells are far more common and given to a variety of different race positions. In that setting, racers can get the items if they are as close as fifth place. The item is less common if the settings are changed to "Basic" or "Normal", but are still given to players in lower positions. If a player is targeted for attack by a Spiny Shell or is in the vicinity to be hit by the blast, the player can avoid the attack by means of a Star, Mega Mushroom, Mushroom, or Bullet Bill.

In team races and Battle Mode, the Spiny Shell, as with other items, cannot attack members of the same team. In team races, a Spiny Shell would go after the leader of the opposing team to blow him or her, regardless the place the opponent stays. They are also available to use in Battle Mode, carrying the same function as in team races. In this mode, the shell will chase after the leading member of the opposing team to take away one balloon, if there is a Balloon Battle in session, or drop several Coins if there is a Coin Runners battle. Players can avoid the explosion by using the aforementioned items above.

Trivia

 * In Mario Hoops 3-on-3, Spiny Shells are known as Angel Shells.