Crystal Cave (Japanese: すいしょうのどうくつ Crystal Cave) is a dungeon in Pokémon Mystery Dungeon: Explorers of Time and Explorers of Darkness and Pokémon Mystery Dungeon: Explorers of Sky. It has 11 floors. It is unlocked the day after the player beats the boss in Quicksand Cave.
There seems to be no connection to items and floor.
This dungeon has the same traps as Quicksand Cave.
The puzzle room at the end of Crystal Cave