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[Folklore] The Shellycoat is a Scottish bogeyman who haunts the rivers and streams. He is covered with shells, which rattle when he moves, announcing his presence. He enjoys misleading wanderers and often puts them on the wrong track. The Shellycoat is playful, but rather harmless. Generally, the creatures who inhabit rivers are less dangerous than those who live in lakes and seas.

See more at Wikipedia.org...

[Folklore] The Shellycoat is a Scottish bogeyman who haunts the rivers and streams. He is covered with shells, which rattle when he moves, announcing his presence. He enjoys misleading wanderers and often puts them on the wrong track. The Shellycoat is playful, but rather harmless. Generally, the creatures who inhabit rivers are less dangerous than those who live in lakes and seas.