Cethern mac Fintain
（重定向自Cethern）
Cethern mac Fintain is an Ulster warrior who aids Cúchulainn in the Táin Bó Cuailnge (Cattle Raid of Cooley), according to the Ulster Cycle of Irish mythology.
As Cúchulainn lay wounded after his combat with Ferdiad, Cethern entered the fray on his chariot, stark naked and armed only with a silver spike. He killed many men, but was severely wounded.