Adrastus
Adrastus was a king of Argos, one of the key city-states in the Peloponnesian peninsula. Adrastus was the son of Talaus and Lysimache. Through his lineage, he was connected to several other important figures in Greek mythology, including Oedipus and his descendants.
Adrastus' most famous involvement in Greek mythology comes from his role as the leader of the Seven Against Thebes. This group of heroes banded together to support Polynices, the exiled son of Oedipus, in his attempt to reclaim the throne of Thebes from his brother Eteocles. The conflict stemmed from a curse placed upon their father, Oedipus, which doomed his sons to divide their inheritance (the kingdom of Thebes) by the sword.
Adrastus was the only one of the seven leaders to survive the disastrous campaign against Thebes, a survival attributed to the intervention of his divine horse, Arion, which was a gift from the gods and could run swifter than the wind.
The story of the Epigoni ("the offspring") is a sequel to the tale of the Seven Against Thebes. The children of the original attackers, including Adrastus' sons Aegialeus and Diomedes, launched a second expedition against Thebes to avenge their fathers. This time, the oracle of Delphi had prophesied success, and indeed, the Epigoni were victorious, capturing Thebes ten years after the first attempt. Adrastus saw the fulfillment of the quest he had initiated, albeit posthumously for his son Aegialeus, who died in the battle, mirroring the fate of his companions in the first campaign.