Crysta Cave is an area in Almia. It is located in the northwestern part of the region, between Hia Valley and a river which connects the cave to the Union Road.
The player first goes to the Crysta Cave to visit Hia Valley in search for the Blue Gem. The player needs a Pokémon with the field move River Flow, Floatzel or Empoleon (Empoleon can't be captured before this mission). The player will cross the river with the Pokémon and enters the cave. Team Dim Sun blocks the exit of the cave when first arriving here with a block of ice. The player must catch a Pokémon with the field move burn 3 to remove the block of ice to continue the mission.