Megapenthes (son of Proetus)

In Greek mythology, Megapenthes (Ancient Greek: Μεγαπένθης Megapénthēs means "great sorrow") was a king of Argos.

Family
Megapenthes was the son and successor of Proetus and father of either Argeus or Anaxagoras (in some accounts, Anaxagoras was his grandson through Argeus). He also had a daughter Iphianeira, who married Melampus.

Mythology
Megapenthes exchanged kingdoms (Argos for Tiryns) with his cousin Perseus whom he killed much later.