Toothless~

Colour: wood-brown scales on the body, cream underbelly, blue shades on the main parts of the body.
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Eyes: orange-yellow iris.
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Muzzle: Flattened, owl-like. Two long, spike-like horns protrude from the nose.
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Additional details: There are two scars on the facial spines.
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Wings: Two pairs of wings, one below the other. When all four wings are spread out in an X shape, the dragon becomes very maneuverable. The lower pair of wings can be used for walking, supported by large wing claws.
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Back and tail: covered with sharp spines, those on the back being larger than those on the tail. The tail ends in several flaps.
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Claws: The tips of the wings have sharp, hooked "pincers" that are dexterous enough to carefully pick the lock of a dragon trap or tear apart a war machine.
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Vision: Stormcutters can rotate their heads nearly 180 degrees, providing a wide field of vision.

Coloring. His entire body is covered in jet-black scales. Interestingly, in the first film, there were small light spots on his sides and wings with a pattern reminiscent of a manta ray. But by the second film, these spots had faded, and by the third, they had completely disappeared, leaving Toothless's coloring solid and completely black.
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Wings. It has two pairs: one main pair (which allows for vertical takeoff) and a second, smaller pair at the base of the tail (which helps with gliding).
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Eyes. Bright green, sometimes with an acid or emerald tint. They are positioned fairly close to the front of the face, giving the dragon excellent depth perception and quick reflexes in flight. Another interesting detail: Toothless can change his pupils. When threatened or angry, his pupils narrow to slits—just like a cat's. And when calm, happy, or docile, his pupils dilate and become more dog-like.
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Build and other features. The body is slender, with a short neck. Its head has eight appendages that function as ears and are capable of detecting ultrasonic sounds. The legs are short, and the tongue is long and unforked. Its back has a row of elongated spines. These aid in sharp turns. The tail used to have two natural fins at the end for steering and stability, but after Hiccup shot down the dragon with his Mangler, the left side of the tail fin was lost. Hiccup later constructed a mechanical prosthetic fin for it, which Toothless sometimes wears along with a homemade saddle. The dragon also has two noticeable scars: a large one on its right shoulder/neck (about a foot long and an inch wide) and a smaller one on its left foreleg.
He's very sensitive and loves playing with Thunderwing, sometimes pestering him, and can climb on him or hide under his wing without asking.