Caves in Pikmin 2 are made out of randomly placed units. There are units that represent dead ends, corridors, crossings, and rooms. Every cave's sublevel has a list of units that can be used by the game to create it; the latter is then responsible to randomly align the units in order to create a level with no unconnected exits.
There are three types of units, as defined by the "room type" property, declared in the sublevel unit definition text files:
In 2-Player Battle, for all caves excluding the Dim Labyrinth, there is a static list of units to use, as well as their position and rotation. Instead of the game generating a cave using the available units, it only has to pick one of the available static layouts. These static layouts can be found in
The following is a list of all existing units in Pikmin 2, used and unused, and sorted by theme. The themes are named based on the common word in the units' names.
Units in the concrete theme have their names end with "conc", which is likely short for コンクリート? (lit.: "concrete"); this word comes from the concrete walls that these units have.
Units in the garden theme have have their names end with "kusachi" (草地?, lit.: "meadow").
Units in the metal theme have their names end with "metal".
Units in the snow theme have their names end with "snow" or "renga" (レンガ?, lit.: "brick"), due to the brick walls they have.
Units in the soil theme have their names end with "tsuchi" (つち?, lit.: "soil").
Units in the toybox theme have their names end with "toy".
Units in the tiles theme have their names end with "pipe" or "tile".
Pathways with items
The following units are copies of the regular pathway units, but presumed to have items (normally eggs) in them, judging by the names. All of these are unused.
These units are near duplicates of existing units, differing only on certain internal files. These duplicates could exist for a variety of reasons, but most of the time, it's to change the general layout of an existing unit, for the purposes of the cave or the objects within.
As with the previous section, these units are near duplicates of existing units, but with layout.txt changed to fit the 2-Player Battle arenas.