Mario Kart 8 Deluxe – Booster Course Pass

The Mario Kart 8 Deluxe – Booster Course Pass is a DLC expansion pack for Mario Kart 8 Deluxe, announced during a Nintendo Direct held on February 9, 2022. The pack includes 12 additional cups, for a total of 48 additional courses (bringing the total number of courses to 96), most of which are remastered versions of courses from other Mario Kart games, including Mario Kart Tour. The courses are based on their designs from Mario Kart Tour, with the exceptions of and, which are currently absent from said game. However, the courses have received visual improvements and new music arrangements compared to Mario Kart Tour. The pack marks the longest gap between the original release of a Mario game and the release of its DLC, releasing nearly five years after Mario Kart 8 Deluxe did. The pack also makes Mario Kart 8 Deluxe the first Mario Kart game to feature classic courses from games following the original game's release, with Mario Kart Tour and its reappearing courses debuting after 8 Deluxe was initially released.

The pack is set to be released in six waves by the end of 2023. It can be purchased on its own, but is also included in the Nintendo Switch Online + Expansion Pack membership. The first wave of the DLC was made available to pre-load on March 15, 2022, and was released on March 18, 2022. The second wave was released on August 4, 2022. If the player has purchased the Booster Course Pass or currently has a Nintendo Switch Online + Expansion Pack membership, a small icon of a Super Star can be seen next to the version number on the game's title screen.

The courses shown in the key artwork use official screenshots and in-game course icons from Mario Kart Tour. Some screenshots of the courses show Paris Promenade and Paris Promenade 3 with barrier fences from that game. The artwork also features an official screenshot of the ninja Shy Guys in Ninja Hideaway, which originated from the Ninja Tour's in-game preview. Some promotional material for Wave 1, primarily the infographic showing all the courses in the wave, also used Tour screenshots. However, Wave 2 used in-game screenshots from 8 Deluxe for every course in both waves.

Several minor adjustments to the courses in Wave 1 were made upon the release of Wave 2, such as their course icons being slightly brighter, and the sand and dirt on some courses now leaving tire marks. Additionally, the final car section in was adjusted, making the cars serve as hazards and move sporadically in random directions (except for in Time Trials, in which they remain stationary). The generic course icons used in place of future waves of the DLC also become mirrored like the normal course icons when playing in Mirror mode.

Courses
Each of the six waves features two cups, each with four courses, for eight courses per wave. As of the second wave, there is one course each from Super Mario Kart and Mario Kart 7, two courses each from Mario Kart 64, Mario Kart: Super Circuit, Mario Kart DS, and Mario Kart Wii, five courses from Mario Kart Tour (making Mario Kart 8 Deluxe the first and only game in the series that features classic courses of a Mario Kart game released after it), no courses from Mario Kart: Double Dash!!, and one brand new course. Excluding the Tour courses, DS Shroom Ridge and GBA Snow Land are currently the only courses in the Booster Course Pass that have not previously appeared as classic courses, while Sky-High Sundae is currently the only course to make its series debut in the pass.

Only Mario Kart Tour's city courses are labeled as Tour tracks in-game, as shown by Ninja Hideaway and Sky-High Sundae lacking the Tour prefix.

Internal content
An alternate version of the key artwork exists in the game's files as of version 2.0.0, showing several currently unreleased courses. This banner also uses official screenshots and in-game course icons from Mario Kart Tour, including icons for T and R/T variants. Several tracks included in Wave 2 appear in this banner, including and Sky-High Sundae, though the  art used within it is not that of. Several more appear, though many are too blurry to be properly identified; however, the starting area of, the snowboarding section of , and the underwater portion of all appear.

Among the game's internal data, there exist prefixes for upcoming courses: "SNES" (denoting a Super Mario Kart course) is allocated to one upcoming course, "GBA" (Mario Kart: Super Circuit) to three upcoming courses, "GCN" (Mario Kart: Double Dash!!) to four, "DS" (Mario Kart DS) to two, "Wii" (Mario Kart Wii) to four, "3DS" (Mario Kart 7) to two, and "Tour" (Mario Kart Tour) to 10. There are also six courses without a prefix.

Also present in the game's files as of version 2.1.0 are music snippets for many unreleased courses, including that of all of the original Mario Kart Tour courses up to Tour Bangkok Rush, as well as that of, GBA Boo Lake/Broken Pier, /Wario Colosseum (although the former is seen on the banner), , , , and. Each course is given a dedicated slot, with every Wave 3 cup having been determined, meaning the Rock Cup will feature Tour London Loop, DS Peach Gardens, GBA Boo Lake/Broken Pier, and 3DS Rock Rock Mountain, and the Moon Cup will feature Tour Berlin Byways, GCN Waluigi Stadium/Wario Colosseum, Merry Mountain, and 3DS Rainbow Road. This also aligns with the prefixes present for Wave 3 courses. Additionally, the datamine also reveals the specific slots for Tour Amsterdam Drift, Tour Singapore Speedway and Tour Los Angeles Laps for Wave 4, GBA Sunset Wilds and Tour Bangkok Rush for Wave 5, and Tour Vancouver Velocity and Wii Maple Treeway for Wave 6, lining up with the prefixes present for these respective waves as well.

Trivia

 * The pass was once erroneously referred to as the "Mario Kart 8 Deluxe – Booster Course Pack" on the official North American webpage. This error has since been corrected.
 * The countries of most of the 150cc staff ghosts for Mario Kart Tour's city courses match the cities' respective countries: 's staff ghost is French, 's staff ghost is Japanese and 's is American.
 * 's is an exception, as its staff ghost is Japanese. This is likely because no ghost staff in Mario Kart 8 Deluxe is Australian.