Lucky Seven

The Lucky Seven is a special item that first appeared in Mario Kart 7. It is depicted as a red number "7", matching the one from the game's logo. The name originates from a symbol on slot machines, where three sevens results in a jackpot.

In Mario Kart 8, a very similar item called the Crazy Eight appears, and it functions identically to a Lucky Seven, except it gives the player eight items instead of seven (with the eighth item being a Coin).

Mario Kart 7
The Lucky Seven debuts in Mario Kart 7. It is one of the items that can be found from the Item Boxes by racers in approximately fourth to seventh place, with a rarity on par with the Spiny Shell. When used, seven items appear surrounding the racer's kart rotating similarly to the Triple Green or Red Shells. The racer can then use them one by one; the item used is the one closest to the front of the kart. The Lucky Seven contains the following items; a Banana, a Green Shell, a Red Shell, a Mushroom, a Star, a Blooper, and a Bob-omb. If the item settings in VS or Battle modes are set to Shells Only, Bananas Only, Mushrooms Only, or Bob-ombs Only, then all seven items will be the dominant item. If Shells Only is on, the player will have seven Red Shells.

Like Triple Green or Red Shells, opposing racers that get too close are hit by the circling items. As one would expect, a Banana or Shell simply hits the opponent, while Mushrooms or Stars give opponents their boost, and a Bob-omb explodes and takes out any items that had yet to be used. A collision with the Blooper will put a single splotch of ink on the opponent's screen.

In normal racing, only the player characters can use the Lucky Seven, similar to how Triple Red Shells are normally a player exclusive item. In other item settings in VS or Battle Mode, however, CPUs are able to get the Lucky Seven.

Mario Kart Tour
The Lucky Seven returns in Mario Kart Tour, but with the Star replaced by the Super Horn. It is the special item of King Boo, Pauline, Daisy (Holiday Cheer), Luigi (Classic), Mario (Chef), Mario (Halloween), Nabbit, and Lakitu (Party Time). This time, all the items are used all at once, rather than one at a time. When Lucky Seven+ is active, three coins are added to the mix of items.

Mario Kart 7

 * Instruction manual bio: "Press or  to surround your kart with seven items, and then press  or  again to use them one at a time."
 * North American website bio: "You're in luck now! This wild new item will give you a full-on smorgasbord of items to use all at once."

Mario Kart Tour

 * Tips & Tricks: "Seven items (Red Shell, Banana, Green Shell, Bob-omb, Super Horn, Mushroom, and Blooper) revolve around your kart. Tap the screen to use all seven items at once."
 * Mario Kart Tour Twitter: "Pauline's Lucky Seven special skill makes her a force to be reckoned with! When used, Lucky Seven overwhelms your opponents with a sudden surge of seven different items at once! Who knew this refined mayor would wield such a perfectly preposterous item!"

Trivia

 * If the Lucky Seven is active underwater, the Blooper will leave a trail of ink bubbles.
 * The image in the roulette retains the checkerboard background, being the only item to have a background of its own in the roulette.
 * When the Lucky Seven is received, it plays the sound effect heard when receiving a powerful item like a Star in Mario Kart DS.