Crystal Castle, frequently called CC by players, is a dungeon located within Winden, specifically northwest of Snowbasin Town. Its main types are Ghost and Ice. It is found after the player travels through Crystal Ruins. Crystal Castle is known for its Sealed Chamber (containing a box which may contain Clear Silk) and Reviver Seeds, an item that is always in demand.
The Pokémon in this dungeon are mainly in the level range of 41-46, but Regice is level 60, and Bronzor and Gastly are lower than 35.
Darkness surrounds the player for the entire dungeon, even the boss room. Snow or hail is the weather for most of the floors. Water is common on the floors, but in small quantities. The water has a special effect that if any non Ice-type steps on it, they freeze (preventable with Safeguard or an Aspear item).
All Pokémon with the exception of Regice spawn naturally and randomly. If there is a Regice on the floor, then the screen will display a message at the bottom. There is no guarantee that a player will encounter a Regice on his or her journey.
- Regice (Random)
The main boss room has 2 mini-bosses and a main boss. They all attack at the same time.
- 2 Haunters (Mini-Boss)
- Froslass (Boss)
- Frozen Oran
- Colbur Berry
- King's Rock (Walls)
- Trapped Scarf (Walls)
- TM Will-O-Wisp
- TM Hail
- TM Ice Beam (Regice Rare Drop)
- Ice Diamond (Regice Common Drop)
- Tiny Mushroom (Froslass Boss Drop)
- Icicle Plate (Froslass Boss Drop)
- Reviver Seed
As with most dungeons, the goal is to complete it. The TM Ice Beam that Regice rarely drops is also a very valuable item for players. Same applies to Icicle Plate rarely dropped by Froslass. Regice can drop its Heart Slate, which allows it to be summoned in a dungeon if Regice's Heart Slate is combined with the Mystery Part.
Crystal Castle is also a location in which Clear Silk can be obtained. This can be accomplished by unlocking the Sealed Chamber on 5F with a Silver Key and having the contents of the box contained appraised.