By other accounts, he was maternal uncle of Ravana and Kaikesi's brother.
Prahasta leds Ravana's army in the wars against Yama, Kubera and the Devas, and the Asuras and Daityas, through which Ravana establishes his sovereignty over the three worlds. He also leads the initial Lankan response to the invasion led by Rama, Lakshmana, Sugriva and the Vanara Army.
Prahasta is slain by Rama during the Ramayana war.
Prahasta was actually killed by Rama's younger brother, Lakhsman on day one of the battle.