Mario Kart 8 originally launched back on the Wii U all the way back in May 2014, meaning that it's been entertaining fans for almost a whole decade now. Mario Kart 8 Deluxe's release on the Nintendo Switch in 2017 gave the game the life it truly deserved, bringing a handful of new features and quality-of-life upgrades that have kept fans coming back time and time again for years. Mario Kart 8 Deluxe is currently the best-selling Nintendo Switch game of all time, and it's going to take something very special to top it.

Every so often, a new Mario Kart entry will try to switch up the usual formula by adding some kind of new gimmick. Mario Kart: Double Dash!! Added dual drivers, Mario Kart 7 added underwater and flying segments, and Mario Kart 8 added anti-gravity portions of tracks. Though these gimmicks aren't usually too abrasive, an eventual Mario Kart 9 might need something a bit bolder to convince the casual market to hop on board once again. Some new mechanic could end up being teased in Mario Kart 8 Deluxe's Booster Course Pass DLC.

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Mario Kart 8 Deluxe's Final DLC Tracks Could Act as a Testing Ground for Mario Kart 9's Mechanics

It's not every day a new character is announced for Mario Kart 8 Deluxe, but the return of Birdo seems might be just the beginning of DLC characters.

When Mario Kart 8 Deluxe's Booster Course Pass DLC was first announced back in February of last year, fans were a little shocked. This marked the first real DLC made for Mario Kart 8 Deluxe, and it was coming five years after the game's launch on the Switch. This wasn't just a few extra tracks either; Mario Kart 8 Deluxe's Booster Course Pass promised six waves of content, with eight tracks in each wave, spread across the next two years. It was oddly ambitious, but it's a move that seems to have paid off for Nintendo.

Mario Kart 8 Deluxe's Booster Course Pass has just received its fourth wave, with another eight tracks coming to the game along with a new playable character for the first time since launch, with longtime Mario character Birdo getting the lucky spot. There are two waves left to come for the Booster Course Pass, and though no official release dates have been given, one will likely drop in mid-summer, and then the other will arrive at the end of 2023.

In terms of content, the next two waves of Mario Kart 8 Deluxe's Booster Course Pass DLC are expected to follow a near-identical pattern to the last four. Another eight new tracks will come with each wave, all likely being remakes of classic courses from across Mario Kart history. If players are lucky then they may even get another completely original track or two. Signs suggest that players can look forward to new playable Mario Kart drivers in future waves too.

What would be really great is if Mario Kart 8 Deluxe's final Booster Course Pass wave teased some potential mechanics for Mario Kart 9. Gimmicks are a frequent occurrence in the Mario Kart franchise, and it seems likely that Mario Kart 9 will have at least one. It would be smart for Nintendo to use the final Booster Course Pass wave as a testing ground for some of these potential mechanics, being able to immediately see fan reactions before implementing them in the next mainline entry. It's unclear what new mechanics Mario Kart 9 will have, but it might be interesting to see some kind of shifting course mechanic, whereby some of the track's elements move around during the course of the race, requiring even veteran Mario Kart players to pay attention at all times.

Mario Kart 8 Deluxe is available on the Nintendo Switch.

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