Monstrous Nightmare

A Monstrous Nightmare (Wyveromimus Deinocus) is an extinct dragon that lived in what is now western Russia and Eastern Europe. They were almost twice the size of a Night Fury in height and length, but weighed about the same as an adult and a yearling Night Fury. This species may have been responsible for myths and stories of dragons that had a similar sppearance, for example, the dragon from Sleeping Beauty. They were carnivorous and most likely fed on wild bovids and deer. Like most dragons of the post-KT Earth, they had six limbs consisting four legs and two wings. They were named probably because of their aggression.

Extinction
Like all dragons, Monstrous Nightmares went extinct most likely due to habitat loss from humans for farming livestock, and due to hunting livestock, they were killed off by vikings and knights.

However, as with most dragons, their sightings as live animals continues, even though they are still considered cryptids.