"It resembles a cross between a Deadly Nadder and a Hideous Zippleback. It's head is similar to a Zippleback's, and its body, legs and feet are reminiscent of a Nadder's. It has spines like those of a Zippleback too, and has a long tail.
"Even for infants, Scuttleclaws have proven to be quite powerful. They were able to carry heavy Vikings, such as Gobber and Fishlegs. It also appears they have green fire, though they haven't been seen using it in the second film. Like all baby dragons, Scuttleclaws are immune to the Bewilderbeast's control. Also these infants can fly for a very long distance from their home all the way to Berk, carrying heavy riders and like to show off their stamina."
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