Cehuetzi

Its fangs glint in the light as if they were of pure platinum, its flesh like a plate of armor forged of the hardest steel. Yet with only scattered sightings having been reported, none are sure which of the stories are true and which are overblown hyperbole.

Its breath is said to call forth blizzards from still winds, sending out icicles like lances made of diamonds, piercing the earth and littering it with myriad shards of glass.

If you hear its roars, then it's already too late. It stalks its prey in the cold of night, allowing for no rest or hope of escape.