The Jackal Mastiff was seen in Star Trek VI: The Undiscovered Country, as guard dogs on Rura Penthe. I’ve used additional information from Star Trek Online for this creature. They are Klingon guard animals, with many similarities to Earth canines. They are arctic creatures, with white fur and a large protruding tooth that follows their nose line. They are pack animals, and attack with their bites. They are hard to see in snowy environments due to their natural camouflage.