Muirselche
The Irish name means sea snails but the Muirselche is probably a giant octopus or cuttlefish. Its chief ability is to suck things and people into a huge maw that was like a treasure bag or repository. It could suck in an armoured man. It was finally overcome by the Dagda, the good god, with his club of the tempest, who chanted a spell against the Muirselche causing it to ebb away. The words were “Turn your hollow head, turn your greedy treasure-seeking body, turn your crest, turn your death dealing darkness, turn!”
John and Caitlin Matthews, The Element Encyclopaedia of Magical Creatures, 2013, Muirselche, p 333
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