Lycus was killed by Derkus Petronicus. According to Derk, Lycus killed the sons of a woman, who in turn hired him to kill him. Hercules claimed to have known Lycus a long time and had never known him to kill anyone. Derk believed that because of Lycus, there was a family in Attica without any male heirs. When Hercules pointed out that courts decide guilt and punishment not mercenaries, Derk responded that the courts did not punish Lycus, so he did so.