Lets go over the basic game types.
The real single player of the game. Pits you against 11 other computer players in a free-for-all race. You race on four tracks in a row (called a “Cup”) and score points based on what position you finish in each race. Person with the most points wins the gold, second is silver, and third gets bronze.
Here you can set place times. You race against no one, just yourself. There are not items, you only start with three mushrooms. The object here is to set the best time possible on any track you want. You can also race against “ghosts” (other people that have completed the track with a good time) to see how you fair.
Basically the same as Grand Prix, only you get to chose the tracks you want. Four tracks from any cup in any order. You can race alone, or team up with 6 other computers. Team races pools your teams score against the other teams. The team with the most combined points wins.
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A very fun mode. Your objective is to beat the tar out of the other team using items. You don't play normal tracks, rather they set up a sort of deathmatch arena. After a person loses all three balloons, their team loses a point. If you knock a balloon off of another player, you gain a point. There is no friendly fire, so you cant hurt your team mates. Battles are fought best two out of three. After you win or lose a match, you'll pick another arena and fight again until one of you has two wins.
Pretty much the same as Balloon Battle, only when you hit an opponent they drop a coin. Collect it to get a point. Team with the most points at the end wins. They are still best two out of three.