Using Gastro Acid, Mummy, etc
In theory, it would, but there is no way to cancel out Multitype. It's not affected by moves like Gastro Acid or Worry Seed, nor will Mummy have any effect on it. Since there is no legitimate means of canceling Multitype, the answer to your question is no.
http://bulbapedia.bulbagarden.net/wiki/Multitype_%28ability%29
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