Dussehra might be a festival to celebrate the victory of good over evil, but it's only a minor part of Hindu mythology. Ravan was one of the most important characters ever in the scheme of things. He's seen mostly as a villain, but surely he's much more than that.
During the birth of his son Meghnad, Ravan 'instructed' the planets to stay in the 11th house of the child, which would grant him immortality. Saturn, or Shani, refused to do so and stood in the 12th house instead. It irked Ravan so much, it is said that he attacked Shani Dev with his mace and even imprisoned him.
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Most powerful Asuras (demons) knew that they were sent to earth to perform a particular role. Ravan knew that it was his fate to die by the hands of an avatar of Vishnu, something that would help him attain moksha and give up his demon form.
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