If you are wondering why is there a different Mismagius, it a Aevian Mismagius from Pokemon Rejuvenation. To get Aevian Mismagius, you have type in the password aevianmissy (you could do it at the start of game or get data chips through hidden spots, the orphanage, or 7th street market.), go to a hole in Rhodochrine Jungle, find Aevian Misdreavus, capture it, and evolve it through a leaf stone. Spoilers: A certain character will appear during the Post Game.
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