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 in the game to 96), most of which are remastered versions of courses from other Mario Kart games, including Mario Kart Tour. The courses also received new music arrangements and visual improvements while being based on their designs from 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. In addition to the courses, starting with Wave 4's release, the pass also features additional playable characters for the game, which also return from other Mario Kart games.

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 as well as in the digital-only Mario Kart 8 Deluxe Bundle (Game + Booster Course Pass). In Hong Kong, activation codes for the Booster Course Pass are additionally distributed in physical Nintendo Switch game cases, though buyers must own a copy of the base game to be able to use a code. The first wave of the DLC was made available to pre-load on March 15, 2022, and was released on March 18, 2022. In Mainland China for the Tencent release, waves release later than they do internationally, with the pack set to completely release by the end of 2024 rather than 2023. 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, as well as an official screenshot of the ninja Shy Guys in Ninja Hideaway, which originated from the Ninja Tour's in-game preview. Prior to Wave 1's release, the infographic showing all of the known courses across all six waves also used Tour screenshots. However, in the launch trailer for Wave 1 posted following its release, the infographic was updated to use in-game screenshots from 8 Deluxe for all courses, which the release trailers for future waves would follow as well.

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 as they were originally).

Courses
Each of the six waves features two cups, each with four courses, for eight courses per wave. As of the fourth wave, there is one course each from Super Mario Kart and Mario Kart: Double Dash!!, two courses from Mario Kart 64, three courses from Mario Kart 7, four courses each from Mario Kart: Super Circuit, Mario Kart DS, and Mario Kart Wii, eleven courses from Mario Kart Tour, and two new courses. Excluding the Tour courses, and  are currently the only classic courses in the Booster Course Pass that had not previously appeared as classic courses in other games, while Sky-High Sundae and Yoshi's Island are currently the only courses to make their series debut in the pass.

Ninja Hideaway and Merry Mountain lack the "Tour" prefix, despite both debuting in Mario Kart Tour. Furthermore, despite making its debut in the Booster Course Pass, Sky-High Sundae is labeled and marketed as a new course in both the pass and Mario Kart Tour. In the Tencent release of the DLC in Mainland China, all courses from Mario Kart Tour lack the "Tour" prefix, likely due to Mario Kart Tour's unavailability from app distribution platforms in Mainland China.

In the British English version of the pass, and  are known as  and  respectively, as was the case in the British English versions of their original appearances. However, courses that had different names between European French and Canadian French in previous games instead use their European French names in the pass in both versions.

Characters
Starting in Wave 4, additional playable characters were also added to the Booster Course Pass in addition to the courses, with more returning characters set to be included after Wave 4. It is unconfirmed how many characters will be added in the pass, although there are six additional slots on the character selection screen as of version 2.3.0, meaning the pass will add at least six characters.

Wave 4

 * MKT_Icon_Birdo.png Birdo - Birdo returns as the sole playable character included in Wave 4. Similarly to Yoshi and Shy Guy, Birdo has nine different colors. She is a medium weight driver and has identical statistics to Peach, Daisy, and Yoshi.
 * Alternate colors: MKT_Icon_BirdoOrange.pngMKT_Icon_BirdoYellow.pngMKT_Icon_BirdoBlue.pngMKT_Icon_BirdoLightBlue.pngMKT_Icon_BirdoGreen.pngMKT_Icon_BirdoRed.pngMKT_Icon_BirdoBlack.pngMKT_Icon_BirdoWhite.png

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. As with the official artwork, this banner uses official screenshots and in-game course icons from Mario Kart Tour, including icons for trick and reverse/trick variants. Several courses included in the pass appeared in this banner before their official announcements, including Sky-High Sundae,, , and several Tour city courses (notably including and  before their official reveals for Tour ), though the  art used within it is that of , rather than , which appears in the pass. can be identified in the banner, implying its inclusion in a future wave.

In the game's internal data in version 2.0.0, many upcoming course slots were each designated a prefix. Across waves 2-6, "SNES" (denoting a Super Mario Kart course) was allocated to two courses, "N64" (Mario Kart 64) to one course, "GBA" (Mario Kart: Super Circuit) to four courses, "GCN" (Mario Kart: Double Dash!!) to four, "DS" (Mario Kart DS) to three, "Wii" (Mario Kart Wii) to five, "3DS" (Mario Kart 7) to two, and "Tour" (Mario Kart Tour) to twelve, in addition to seven courses without a prefix. The prefixes, which matched the courses in Wave 2, were removed in version 2.1.0 with that wave's release; however, the lineups of Waves 3 and 4 were slightly different, with several prefixes changing positions within the respective waves, and appearing in place of a planned GCN course in Wave 3.

In version 2.1.0, music snippets for many unreleased courses were added to the game's files, including, , all of Mario Kart Tour's new courses up to , and every course that would go on to be featured in Wave 3. These music snippets all corresponded to the course order dictated by the then-removed unused prefixes; the snippets were removed with Wave 3's release in version 2.2.0. The filenames for several of these music snippets indicate that several courses were moved between waves before their release, such as Waluigi Stadium and Maple Treeway originally being planned for Waves 3 and 6 respectively, and Los Angeles Laps and Bangkok Rush originally being planned for Waves 4 and 5 respectively.

Trivia

 * The official North American webpage for the pass has had numerous errors over time:
 * The pass was once briefly referred to as the "Mario Kart 8 Deluxe – Booster Course Pack" on the site.
 * was once briefly labeled as a 3DS course instead of DS.
 * Following the reveal of Wave 3 and until its release, the website erroneously stated that Wave 3 would be available on December 7, 2023 rather than 2022.
 * Similarly, the British Nintendo eShop page for the Booster Course Pass erroneously states that Wave 3 released on December 8 rather than December 7.
 * Nintendo of America used the British English name for in a tweet, before deleting it and replacing it with the American English name.
 * The countries of most of the 150cc staff ghosts for Mario Kart Tour's city courses match the cities' respective countries:, , , , and ' staff ghosts are French, Japanese, American, British, and German respectively.
 * is the current sole exception, with a Japanese staff ghost rather than an Australian one; no staff ghost in Mario Kart 8 Deluxe is Australian.
 * Unlike the first three waves, the North American version of the reveal trailer for Wave 4 did not have a voiceover, similar to other regions.