What are helpful mutations Has to be a mutation that exists on earth for a fire breathing monkey living in the alpine region?

There are no known monkeys ( it is possible the Abominable Snowman or Yeti might be an anthropoid APE) native to the Alps. Monkeys are generally adapted to warm climates. Fire breathing creatures exist only in myths and Science Fiction of the monster variety. a fire-breathing monkey in the alps, it doesn"t make sense from a zoological standpoint.

*I just need this for a game in my science and Ive run out of ideas all logic like that is dropped*