The parents of the hero Achilles are the mortal king Peleus and the sea nymph Thetis. Their union is significant in Greek mythology as it brings together divine and mortal lineages, which is reflected in Achilles' exceptional strength and prowess in battle. Thetis plays a crucial role in her son's fate and journey, emphasizing themes of destiny, heroism, and the complexities of divine intervention. Achilles is famously known for his role in the Trojan War and his almost invincible nature, save for his one vulnerable spot, creating a poignant exploration of mortality and honor.