Mac Trí Con. Son of Cú Roí and killer of Cúchulainn in the Ulster Cycle, to be distinguished from the similarly named Lugaid mac Con. Although his usual patronymic identifies Lugaid as son of Cú Roí, his alternative patronymic, mac Trí Con or mac na Trí Con, means ‘son of three hounds’, denoting triplism, perhaps Cú Roí, Cúchulainn, and Conall [strong as a wolf] Cearnach. These latter ‘fathers’ seem odd in light of Lugaid's subsequent encounters with them. Storytellers explained Lugaid's lifelong antagonism towards Cúchulainn because of his mother Bláithíne's adultery with the Ulster hero. Lugaid tries to kill Cúchulainn several times before he succeeds. Once he throws his spear and misses, killing Cúchulainn's charioteer Láeg instead. In the Táin Bó Cuailnge [Cattle Raid of Cooley] he is ready to attack again, but seeing Cúchulainn badly wounded from his battle with Ferdiad at the ford, Lugaid relents. Their final combat is described in a tale often known in English as ‘The Death of Cúchulainn’ or Brislech mór Maige Muirthemne [The Great Rout of Mag Muirthemne]. Lugaid first thrusts his javelin through Cúchulainn's bowels but does not kill him. Allowing the hero a death with more dignity, Lugaid permits Cúchulainn to stand by a pillar-stone while he decapitates him. Conall Cearnach subsequently dispatches Lugaid.
See Whitley Stokes, Revue Celtique, 3 (1887), 175–85;A. G. van Hamel, Compert Con Culainn and Other Stories (Dublin, 1933), 69–133;T. P. Cross and C. H. Slover, Ancient Irish Tales (New York, 1936), 333–40.