The crystal cave (also known as Underwater Tunnel level 4) is a semi-hidden dungeon floor below the underwater tunnels. It is densely populated with light crystals which naturally emit light in one of 3 different colors. This is the only place in the game light crystals appear.
Unlike the rest of the tunnels, the crystal caves are populated with very tough enemies you would be unlikely to find up until the deeper floors of the Gloomy Cave. The player is advised to use caution, as three extremely dangerous light crystal golems (one for each color) are guaranteed to spawn on this floor.
Two special rooms will always be found on this level - the first room has two stairs leading up to Underwater Tunnel level 2 and down to the Spider Level, the second one has a guaranteed altar to Silva and the attending priestess Terra.
- Altar to Silva
- Light crystals