You must find all of the scattered space ship parts to leave the planet before the 30 day period. But you're not entirely alone. Little plant-like creatures called Pikmin seem determined to help you.
Pikmin offers up a unique blend of Real-Time Strategy, Adventure, and Puzzle solving aspects. The biggest part of the game is managing your Pikmin. Random objects that you find can be taken back to the Pikmin space ship to produce more Pikmin seeds. Once you pick the Pikmin they will follow you wherever you go (even if it means their demise). The Pikmin carry parts of the space ship back to base camp so they can be re-attached, as well as objects for producing seeds and corpses of dead enemies. Pikmin will swarm enemies and hammer away at them until they die or the enemy dies. You as the captain must employ strategies to make the battle tip in the Pikmin's favor. Not only are there different types of Pikmin (see Pikmin Types below), they also have three stages of growth. Leaf, to Bud, to Flower. The more a Pikmin grows, the stronger and faster it becomes, thus becoming more useful.
Yellow: Good for carrying bombs around. Use these when explosives are needed. Also immune to electricity.
Red: The first type of Pikmin you will encounter, they are fire resistant.
Blue: These Pikmin are the only type that can survive in water.