The hero who completed the Twelve Labors in Greek mythology is Heracles, also known as Hercules in Roman mythology. These labors were a series of formidable tasks assigned to him as penance for killing his family under the influence of madness. The tasks, including slaying the Nemean Lion and capturing the Golden Hind, demonstrated his unmatched strength and heroic qualities. Heracles’ journey represents the struggle against overwhelming odds and the quest for redemption.