Mac Con takes Cormac mac Airt as his foster son, and rules for seven years. He then pronounces a false judgement, showing that he is unfit to rule, while Cormac gives a right judgment, showing that he is the stuff of kings. Disasters ensue—"no grass came through the earth, nor leaf on tree, nor grain in corn" says the story—and Mac Con is deposed and Cormac made king in his place. Mac Con travels to Ailill's court, where his foster-mother warns him that he is in peril. When Ailill embraces Mac Con he bites him with his poison tooth, wounding Mac Con, who flees but is killed by one of Ailill's warriors.