The creature in Greek mythology born from the blood of the castrated Uranus is the Furies, also known as the Erinyes. These vengeful deities symbolize retribution and justice, particularly concerning moral transgressions. Their creation from Uranus's blood underscores the themes of vengeance and the consequences of divine acts. The Furies are tasked with pursuing wrongdoers, ensuring that justice is served, reflecting the belief in accountability woven throughout Greek mythology. Their presence in various myths signifies the intricate relationships between gods, mortals, and justice.