Mahishaasura, who kept transforming from a buffalo, to a lion, to a man, to an elephant, and then back to a buffalo, represents the never ending chain of desires in us. When one desire is fulfilled another springs and takes its place. There is a never ending transformation and multiplication of multifarious desires. This is called Vikshepa Shakti and its rooted in Rajo Guna or Rajas. This conquest of Mahishasura is symbolic to winning over the rajasic tendencies in us.
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