In Pikmin 2, there are 14 caves, which all consist of a number of sublevels, ranging from two to fifteen. Upon entering the cave, you start on the first sublevel with your Pikmin; to progress, you must find the cave that leads down to the next sublevel. A geyser is always found on the final floor, often along with a boss, though geysers are also found at intervals throughout longer and more challenging caves, such as Subterranean Complex and Submerged Castle. These allow you to return to the surface of the Pikmin Planet.
The game contains a variety of sublevel types, in terms of both appearance and function. Firstly, there are normal levels, rest levels and boss levels, each presenting a variation in terms of challenge and gameplay; rest levels contain only harmless enemies, Candypop Buds and eggs, and serve as a place to recover, as it were, from the cave's horrors, and to prepare for the challenges ahead. Sublevels can be floating platforms; more seemingly underground, cave-like areas; or wide open spaces in the style of the Brawl Yard, which would at first glance appear to be above ground.