Because this subject has no official name, the name "Clog" is conjectural.

A clog is an obstacle used to block the entrance of caves and geysers and to plug holes underwater so that areas remain flooded. They can be destroyed with Pikmin; often, only Blue Pikmin are able to approach them due to their being submerged. By destroying an underwater clog, a hole is opened up that drains the water from the surrounding area.

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