MUD: FIM Motocross World Championship is a racing motocross (offroad) motorycle game which focuses more on action than simulation. It is licensed and features the original teams, vehicles, courses and athletes from the FIM Championship.

The heart of the game is the Mud World Tour, which is basically a career mode. By being successful at events (either normal races with 16 athletes, checkpoint races, elimination races, a head to head race with two drivers or freestyle/trick events), the player earns money which can be invested into improving the driver's statistics (endurance, instinct, mobility and strength), equipment (e.g. energy drinks which give a speed boost), the next events, switching to a better team or unlocking the three other drivers. Each driver is a specialists for a certain events which results in more price money.

The other playing modes are single races, playing the Championship (either MX1, MX2 or custom) or participating in freestyle events in which the player needs to perform stunts in order to gain points. In the regular races, tricks only plays a small role because there is only one to perform: when the bike is in the air, the player can press a button with the right timing. With correct timing, a scrub is performed along with a speed boost; when it is screwed up it results in a Whip without advantages. Multiplayer allows for races with up to 12 players.

In the PS Vita version, there are only half the machines in each race (6 in multiplayer and 8 in single-player races)