The Tuatha established their court at Tara, with Nuada as king. In the first battle of Mag Tuired fought against the Firbolg, Nuada lost an arm and, now imperfect, could no longer serve as king. Dian Cecht replaced Nuada’s lost arm with a silver one. Dian Cecht’s son Miach would later replace the silver one with a new real one.

In a second battle of Mag Tuired, the Tuatha, led by the repaired Nuada and later by Lugh, fought the Fomorians, who had returned to Ireland. In a terrible struggle, King Nuada and his warrior queen Macha were killed by the monstrous one-eyed Fomorian Balar, whose glance could kill armies. When Lugh pierced the eye with a slingshot, the eye was turned around so that its powers were turned on the Fomorians, destroying them once and for all.