His rule was preceded by the regency of Nycteus and in turn, Lycus was succeeded by the twins Amphion and Zethus.
Pausanias writes that Nycteus waged war on Epopeus, but in battle was wounded, and died after being carried back to Thebes, appointing Lycus as regent for Labdacus.
Epopeus died of a wound just as Nycteus did, and his heir Lamedon gave Antiope up freely to avoid war.
Nycteus killed himself from shame when he discovered Antiope's pregnancy, and Lycus initiated the attack because he himself desired to punish her, successfully carrying her off after the battle.
[1] In either case, Antiope gave birth to the twins Amphion and Zethus on the way back to Thebes, at Mount Cithaeron.