Wyvern from Amber's Dragon Lair.
Wyverns are highly aggressive and predatory creatures. They're found in the medieval bestiaries of Europe, noticeably those of England and France.  Believed that a wyvern will destroy whatever it comes upon,  they are considered malevolent and dangerous and slain on sight.
In heraldry, the Wyvern is often spelled Wivern, and it is considered a class of dragon in European legends.  Often those with crests depicting a Wivern have a legend of some family member slaying a Wyvern.
The Wyvern has the body of a serpent, the head of a dragon, the wings of a bat, and a long serpent's tail.  The two legs are sometimes that of a lizard but sometimes those of a bird.  The dragon's head is described to be wedge-shaped like that of a crocodile.
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