Nintendo has released version 4.0.0 of Mario Kart 8 Deluxe, a free Switch 2 upgrade for the game that originally launched on Nintendo Switch in April 2017 and traces back to 2014's Wii U release. According to Polygon, the game has around 71 million players. The update arrives more than a year after Switch 2's launch and brings a set of enhancements built around the new hardware.

The headline addition is expanded local multiplayer: Mario Kart 8 Deluxe now supports five to eight players in split-screen on Switch 2, up from a maximum of four on the original Switch. Players can connect up to seven Nintendo Switch controllers (Joy-Cons or Pro Controllers), though at least one Joy-Con 2 or Nintendo Switch 2 Pro Controller is required to reach eight-player mode. Kotaku noted that eight-player races can apparently even be played in handheld mode.

Beyond multiplayer, the update adds support for the Nintendo Switch 2 display and high-resolution TVs for clearer visuals, and shortens loading times before races and battles. The game also gains CameraPlay support for players with a compatible USB camera, usable in Multiplayer (2-4 players) and Online Play, with footage and audio shared through GameChat sessions.

Nintendo made a few gameplay adjustments as well: player speed during races has been increased by the equivalent of one coin, and using Boo to turn invisible no longer slows players down, even when driving through offroad areas. Players who own the Booster Course Pass DLC also gained a new '96 Races' option in VS Race settings, covering all 96 courses across the base game and its six-part, 48-course DLC.

Coverage from Kotaku and GamesRadar+ framed the update against the more recent Mario Kart World, which some described as feeling content-light or unfinished by comparison. GamesRadar+ noted Mario Kart World received two new Knockout Tour routes at the start of July but has otherwise seen less support, and pointed out that Mario Kart 8 Deluxe has historically outsold its successor. Polygon added that, given Mario Kart 8 Deluxe's roughly decade of continued support, Switch 2 owners might hope for similar long-term treatment for Mario Kart World.

An IGN article on the topic was referenced among coverage of the update, but its content could not be retrieved for this summary.