Like Heracles he was precociously strong. In one incident, aged six, he killed the ferocious guard dog of Culainn the blacksmith. In recompense he himself guarded the Culainn's forge until a new dog could be found, earning himself the name CuChulain (Culainn's Hound).
He mastered the javelin and hurley and the salmon-leap, and became a great warrior, whose fury in battle could only be cooled by being immersed in icy water three times or by being confronted by a legion of bare-breasted women. At 17 he fought the entire army of Connacht and her allies, but at 27 he was killed near Slieve Fuad by Lewy.
CuChulain corresponds to Gawain, Siegfried and Achilles in English, Germanic, and Greek tradition.