Rumors suggest that Mario Kart 9 will be very different from its predecessors in terms of its list of playable characters. Nintendo may have plans to cross Mario Kart over with various other Nintendo franchises to diversify the roster. Although the specific plan is surprising, the general idea isn't; the Mario Kart character roster is a flexible but fundamental part of the franchise that's rich for positive change. While Nintendo is possible working on creating change through the character roster, it should examine some other Mario Kart fundamentals that could use an update. For instance, the list of items available in Mario Kart could use an upgrade in Mario Kart 9.

Mario Kart has generally worked with the same pool of basic Super Mario-themed items for many years now, but each game has at least a few special additions. While Mario Kart 9's items could include various references to other Nintendo franchises, ideally it'll tap into the Super Mario franchise too. There are a lot of semi-obscure Super Mario power-ups that seem like they could be a lot of fun in Mario Kart 9, especially thanks to the creative new courses that star in Mario Kart nowadays. Mario Kart owes everything to Super Mario, after all, so it should make use of its source material as best it can.

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Super Mario Bros. 3's Frog Suit

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The third Super Mario Bros. game featured quite a few unique power-ups that Mario and Luigi could use, like the Hammer Suit and the Tanooki Suit, but the Frog Suit is simultaneously one of the game's most distinct power-ups and one of the most obscure. Generally only found in special locations like Toad Houses, this item was ideal for traversing Super Mario Bros. 3's water levels, thanks to its increased swimming power. Mario Kart frequently features underwater levels nowadays, meaning the Frog Suit could prove useful to Mario Kart drivers. The Frog Suit could provide a constant speed boost while the player is in water while additionally increasing the height they get when jumping off ramps.

Super Mario Galaxy 2's Rock Mushroom

The small 3D planets of Super Mario Galaxy allowed for all kinds of unique platforming challenges, as well as special items that made good use of quickly curving planets. The Rock Mushroom from Super Mario Galaxy 2 was one such item, allowing Mario to transform into a rolling boulder that could crush enemies and objects. Rock Mushrooms could be extremely useful in Mario Kart through both power and durability. Using it could transform the player into huge rock for a few seconds, allowing them to knock enemies aside to get an advantage. While they're in this for, Mario Kart racers might be tough enough to ignore small obstacles and incoming Shells, making the Rock Mushroom as useful defensively as it is offensively.

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New Super Mario Bros.'s Penguin Suit

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Technically Mario Kart already has an ice-themed powerup in the form of Mario Kart Tour's Ice Flower, but the Penguin Suit from the New Super Mario Bros. games could provide an upgraded version of the ability in Mario Kart 9. Mario Kart Tour characters who use the Ice Flower can freeze opponents solid by hitting them with icy projectiles, and while the Penguin Suit could give characters that ability, it could also briefly give players better traction on slippery surfaces like ice. Much like the Frog Suit, the Penguin Suit could be extremely helpful when navigating the environments of certain Mario Kart courses.

These are only a few of the Super Mario items that haven't made their way into Mario Kart just yet. The franchise is full of unique abilities that could introduce some valuable variety to Mario Kart races. These items may not necessarily have good odds of appearing in the rumored Mario Kart 9, but their traits make them more than worthy of an appearance. Hopefully Nintendo plays into Super Mario nostalgia a little while assembling Mario Kart 9's roster of items.

Mario Kart 9 is rumored to be in development.

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