The Submerged Castle is a cave in Pikmin 2 in the Perplexing Pool. It is submerged underwater in a lake that cannot be drained and, so, can only be entered with Blue Pikmin; if any other Pikmin are brought to the entrance, the game does not let them enter. The boss of the cave is the Waterwraith, who appears on every sublevel, falling from the sky after five minutes and proceeding to roll around. It is invincible without Purple Pikmin, for which there are Violet Candypop Buds on the final sublevel, so it cannot be harmed and poses quite a threat. Other hazards in the cave include Blowhogs, a Fiery Bulblax and Anode Beetles.