Wedding of Thetis and Peleus
The prophesy that mentions the Olympian order and a heavenly love match is the origin of the Trojan War. Years before the Trojan War started, Poseidon and Zeus fell in love with Thetis, a lovely sea nymph. When they learned about the repercussions of their potential deeds, they both decided against taking Thetis as their wife. According to legend, if Thetis, the sea goddess, had a child with Zeus or one of his brothers, she would have a royal son who would be more powerful than his father and hold a weapon more potent than the trident or thunderbolt. Thetis would wed King Peleus, "the holiest man dwelling on the plain of Iolcus," since Zeus didn't want to take any chances.
Zeus purposefully weds Leda, a sea nymph, to King Peleus, an aged human God, once the weight of the prophecy sinks in. When Thetis gave birth to Achilles, their union was finally complete. Achilles, Helen's stepbrother, had a reputation for being a brave person during the Greek and Trojan Wars. His name is a byword for wartime heroes, particularly in the Trojan War for his murderous rampage that resulted in the decapitation of countless thousands of warriors over 10 years.
He plays a crucial role during the conflict for several reasons. The only warrior to defeat Hector of Troy with unmatched gallantry was Achilles. Achilles is also blamed for the deaths of thousands of Achaean troops due to his disagreement with the ruler Agamemnon and his decision to stop fighting the war.