Eris is the Greek Goddess of discord.

The story that Eris is famous for occurred at the wedding of Peleus and Thetis. The couple decided not to invite Eris to their wedding, knowing that she had a reputation for mischief. Eris, outraged that he hadn't been invited, decided to make a visit to the ceremony to cause a scene. She created a solid gold apple, and on the apple she inscribed "KALLISTI", or "To the fairest". After tossing the apple in the middle of the banquet hall, Eris took her exit.

The other Goddesses attending (Hera, Athena, and Aphrodite) quickly noticed the apple, and after reading the inscription, began claiming it for themselves. As the argument escalated, Zeus summoned the mortal at the party: Paris, prince of Troy. Paris agreed to judge the rightful owner of the apple.

Each Goddess pulled Paris aside one at a time and promised him wonderful things in exchange for his decision in their favor. Hera promised him power, Athena promised him wealth, and Aphrodite promised the most beautiful woman in the world. Paris, young and single-minded, quickly decided and sided with Aphrodite. She promised that Helen of Sparta, wife of Menelaus, would be his wife. Paris soon prepared and set off for Sparta to capture Helen, who came willingly back to Troy with him. Menelaus would not let this deed go unpunished.

Eris, by means of a simple golden apple, set in motion the Trojan War...