Described as the brother or uncle of Cú Roí. He avenges that hero's ‘death’, but he is really Cú Roí revivus. Later the figure known as Conganchnes is slain by Celtchair mac Uthechair. Niam (2), Celtchair's daughter, agrees to marry Conganchnes to learn the secret of his seeming invulnerability: that he can be killed only by having spear-points penetrate the soles of his feet and the calves of his legs. Later the blood from Conganchnes' dog Dóelchu kills Celtchair.