Caladbolg ("hard belly", or possibly "hard lightning"), sometimes written Caladcholg ("hard blade"), is the
sword of
Fergus mac Róich from the
Ulster Cycle of
Irish mythology. Spelled Caladcholg, it is also associated with the more obscure Ulster hero
Fergus mac Leda, suggesting a conflation of two legends. It was said to be a two-handed sword that made a circle like an arc of rainbow when swung, and to have the power to slice the tops off hills and take out several men.
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[Folklore] "Hard-belly". A legendary Irish sword, capable of consuming everything.