In Diddy Kong Racing, players can choose one of ten characters, two of which must be unlocked,[2] who have access to three different vehicles: car, hovercraft and aeroplane.[3][4] The car is an all-round vehicle; however, it is the slowest on surfaces such as sand and water.[3] The hovercraft is designed for both sand and water areas but lacks in acceleration and maneuverability.[3][5] The aeroplane is designed to access aerial areas; it is good at acceleration and maneuvering; however, it has the slowest speed.[3] Each racetrack has a set of boosters known as "zippers" that temporarily boost the player's speed, as well as featuring regenerating balloons of various colours that provide power-ups.[6] There are five different types of balloons: red, blue, green, yellow, and rainbow. Red balloons grant missiles to attack racers ahead, blue balloons grant a speed boost, yellow balloons grant shields to protect the player from attacks, green balloons grant deployable traps to delay other racers, and rainbow balloons grant a magnet ability that brings the player closer to the nearest racer.[3][5] If multiple balloons of the same colour are picked up, the power-up will be upgraded to a more powerful version.[6] A total of two upgrades are available for each balloon.[5] Additionally, racetracks contain non-regenerating bananas that add to speed when they are picked up. A maximum of ten bananas will improve the speed but can also be obtained to prevent other players from gaining speed. If a racer gets hit, two bananas will be deducted.[7]
In "Adventure Mode", players control the racer of their choice to progress through the story. Players begin on Timber's Island, which consists of five interconnected worlds; Dino Domain, Snowflake Mountain, Sherbet Island, Dragon Forest, and Future Fun Land.[3] The worlds are opened up by collecting balloons, except for Future Fun Land, which is a hidden world reached by accomplishing several secret objectives.[5] Each world contains four race tracks, an unlockable battle stage and a race against a boss character. If the player defeats Wizpig in Future Fun Land, obtains all amulet pieces and collect all of the gold medals, the player will be able to play in a mode called "Adventure 2".[3][6] In this mode, all of the balloons change colour to platinum and the tracks are inverted from left to right.[3] The game also features four battle modes which consist of two deathmatch maps, a capture-the-flag-style battle and a mode which involves opponents capturing eggs.[7] The battle modes are not initially selectable, and must be unlocked by collecting keys hidden in each of the worlds.