The Greek hero who completed twelve labors as punishment for killing his family is Heracles, also known as Hercules in Roman mythology. His labors were a series of nearly impossible tasks imposed by King Eurystheus. Each labor tested his strength, courage, and ingenuity, ultimately solidifying his status as a legendary hero. Heracles' journey symbolizes redemption, personal growth, and the struggle against overwhelming odds, making him a pivotal figure in Greek tales.