mario Kart DS is a racing game developed and published by Nintendo for the Nintendo DS. It is the fifth installment in the series and the first to use Nintendo's free online service, Nintendo Wi-Fi Connection. The game was released in the North America, Australia, and Europe in November 2005, and in Japan in December 2005, and in South Korea in which it is the very first Wi-Fi Connection game launched in April 2007. It was well received critically, scoring an average of 91% from Metacritic. Like other games in the mario Kart series, mario Kart DS involves various characters from various mario games racing each other in go-karts on tracks themed from locations in the mario series. Less realistic physics, and the use of various weapons and or items to achieve victory differentiates kart racing games like mario Kart DS from more realistic racing games. In Grand Prix mode, the player competes against seven computer-controlled racers. There are two Grand Prix in mario Kart DS, each consisting of four cups, and each cup consisting of four race tracks. Nitro GP contains sixteen brand new tracks while Retro GP contains sixteen tracks converted from previous entries in the mario Kart series. There are three engine classes which serve as difficulty levels for the Grand Prix mode: 50cc, 100cc, and 150cc. The higher the engine class, the faster all the karts go. A 150cc Mirror Mode is also an unlockable, in which all the 150cc tracks are flipped horizontally, as if seeing the game in a mirror. Another staple of past mario Kart games, Battle Mode, also makes a return. mario Kart DS is the first mario Kart game to feature 1 Player Battle. Battle modes include the classic Balloon Battle, in which you try to pop everyone else's balloons by attacking them or steal them with mushrooms and eliminate them, or Shine Runners, in which you try to collect the most Shine Sprites. Eventually, players with the least amount of Shine Sprites will be eliminated from the game. In the new Mission Mode, players control a specific character in that character's standard kart, and must perform eight individual missions, whose objectives range from collecting coins to attacking enemies. Players are then ranked based on their performance, and given either an E, D, C, B, A, or one to three stars if the task is completed by a certain time. In order to advance to the next level, players must complete a "boss" task, which is unlocked after all eight of a level's missions are completed. Completing all missions in level 1 through 6 with at least a 1 star rating on each mission opens up a secret 7th level with more challenging missions to complete. It should be noted that there are no missions where one of the unlockable characters is playable. In Time Trial Mode, players try to finish a course in as short a time as possible. Like in previous games, the fastest time will be saved as a ghost (a carbon copy of the player's preformance which can be raced against), but, unlike past games, players are now allowed to save ghosts on all 32 tracks. Players can also collect up to 10 ghosts from friends, and, when fast enough, can race against staff ghosts. In Vs. Mode, eight players can race each other using DS Download Play or multi-card wireless LAN. mario Kart DS also supports online play via Nintendo Wi-Fi Connection. Up to four players can play with a Wi-Fi connection. When all four races are complete, each player also receives one win for any opponent who disconnected during the match -- though if the match cannot be completed due to disconnecting, no wins are given to the remaining player. Disconnecting for a race is looked down on. Of the 32 playable tracks, only 20 are playable during Wi-Fi mode, unless using an Action Replay cheating device. In Japan, Nintendo used the Japanese comedy duo Ninety-nine, as part of their "Hot mario Bros." commercial campaign, to advertise the Wi-Fi multiplayer capability of mario Kart DS. They showed luigi (in Japan) being beaten by players in France, the United States, and Italy.