All that is known is he has an owl mannerism and a second set of wings under his main set that can splay and become an 'X-wing'. His 'X-wings' beat up and down in sync and is probably used for extremely tight turns, maneuvers, and for fighting foes. He has a very muscular and sturdy build; mainly walking on 2 legs and his 2 bottom wings. The dragon's face has two long spines that branch off his nose and to the side with a "smashed" face, much like an owl's. On his back he has spikes that resemble the Skrill's. According to the website, the talons on his wings are dexterous enough to pick the lock on a dragon trap, yet sharp enough to destroy Drago's war machines. Cloudjumper has two scars on his facial spines. He also has tentacle-like spiked spines behind his 'eyebrows' which can swivel to become wider when he is curious or fold back when threatened or upset.
He is not a maximum-sized specimen of his race; 9.5m (31feet 3.25 inches) long, 14.6m (48feet) in wingspan, and weighs 2,500 pounds. Based on portraits seen in the films, however, he seems much larger than these measurements, possibly over 22-24m in length and 22m or more in wingspan.
During a dragon raid, Cloudjumper broke into Valka and Stoick's house. Cloudjumper went to the cradle that held Hiccup, Valka and Stoick's baby son. Valka first thought Cloudjumper's intent was to hurt Hiccup, but instead was trying to soothe him by rocking him. Stoick, believing that he wanted to harm Hiccup and Valka, attacked Cloudjumper. However, the house was coming down and Valka was blocked from her husband and child. Cloudjumper saved her from the fire but took her with him, leaving her husband and child wifeless and motherless.
For the next 20 years, Cloudjumper allowed Valka to ride him. Together, they helped save thousands of dragons from Drago Bludvist's trappers such as Eret, and brought them to safety at the Bewilderbeast's nest.
Atfer her attack and rescue on Eret and his men, Cloudjumper and Valka then found a Night Fury being ridden by a boy. Cloudjumper was able to overtake them and make them crash with the help of one of the Dragons from the nest. They then brought the two of them to the Bewilderbeast's nest. Together, Cloudjumper and Valka showed Hiccup a few secrets about dragons. However, Hiccup wanted to find Drago in hopes that could change his mind about dragons. Later, Stoick and Gobber arrived at the nest to rescue Hiccup and Toothless where he discovers that his wife is still alive. After finding her, Stoick asked Valka to come home with him and Hiccup.
The Final Battle
When Drago Bludvist started his attack on the nest, Cloudjumper and Valka rallied the Bewilderbeast and the nest dragons and fought Drago Bludvist's forces with the help of her family and new friends. However, Drago summoned his own Bewilderbeast which killed hers. Cloudjumper and all the other dragons, except the Scuttleclaw babies, were brought under it's control and Drago's. However, when Toothless broke free of it's control and challenged it, Cloudjumper and the other dragons joined him in defeating Drago and his Bewilderbeast. Cloudjumper and the other dragons then bowed their heads in respect of Toothless as the new Alpha Dragon. He now lives with Valka, Hiccup and Toothless on the Isle of Berk.
Cloudjumper is proud and dignified and as a result is not as playful as Toothless, but kind enough to scatter baby dragons away who trifle with Toothless. He is also sensible enough to support Valka in many occasions without clear communications, which is due to his very strong bond with Valka. Cloudjumper's pride, large size and confidence leads him to believe that he is the top dragon in Valka's mountain, second only to the Bewilderbeast, who is the true King. Though he is mostly serious, he knows how to have fun, such as pouring snow on Toothless. Cloudjumper may look big and tough, but actually he is kind and gentle.
Cloudjumper can shoot a sustained torus of fire in a tornado-shaped. Visit Fire Types for more information.
With Valka as his rider, Cloudjumper is able to understand human commands and sense human emotions. Like Toothless, he is a loyal and understanding dragon.
Cloudjumper broke into Valka's house and took her away after checking out her baby. Besides this, he has been her faithful dragon companion for the past 20 years. Because of this experience, they share a wordless shorthand communication while flying, and Cloudjumper can instinctively know when Valka wants him to attack or move. They share a strong bond that Hiccup admires and it would seem that they have a brother and sister relationship.
Not much is known about this relationship. Stoick threw an axe at Cloudjumper when he thought he was threatening his family, leaving a scar. The two appear not to hold any grudge against each other, knowing that he is Valka's husband and that Stoick wasn't trying to harm her.
Hiccup was actually the first member of the Haddock family Cloudjumper met. When he broke into their house, the large dragon approached Hiccup, who was just a baby at the time. When Cloudjumper rocked the cradle, he accidentally scratched Hiccup, resulting in the small scar on his chin. This encounter, along with watching his mother being taken away, could have led to Hiccup's childhood fear of dragons. Twenty years later, Cloudjumper appears to not recognize Hiccup, but does become close to him. Like Stoick, Hiccup does not hold a grudge against him for taking his mother.
Cloudjumper deeply respects the Bewilderbeast and bows to the king. Valka comments "he must have thought I belonged here"; this indicates that Cloudjumper has likely been under the Bewilderbeast's rule prior to his and Valka's first encounter.
Unlike Toothless, Cloudjumper is very serious, and usually grunts at the Night Fury. The two do become closer over time, and Cloudjumper became something of a big brother-like figure to the Night Fury. This can be seen from time to time like when Toothless tries to catch Cloudjumper's attention and as when Cloudjumper regurgitated some fish for him. Cloudjumper is also very noble and of well‐balanced character, as when Toothless became the new Alpha, the proud Stormcutter was the first to respectfully bow to the younger dragon.
- In some artwork, Cloudjumper's teeth are shaped like pegs instead of menacingly sharpened.
- In his concept art, Cloudjumper looked more like a red Skrill.
- It's unknown why Cloudjumper was in the dragon raids that attacked Berk, as the dragons that were in them served the Red Death. Although, it is possible that Stormcutters used to attack Berk.
- His name is a possible reference to the T-16 Skyhopper from Star Wars. His "X-Wing" formation is also a possible reference to the T-65 X-Wing Starfighter from Star Wars.
- Cloudjumper is the only other dragon shown to have visible scars other than Toothless, which can be seen on his horns. Stoick gave Cloudjumper the scar by throwing an axe at him.
- The scar on his skull isn't necessary from Stoick, as it was seen before Valka even came into the house, when Cloudjumper was shown to walk to Hiccup's crib.
- Cloudjumper accidentally cut Hiccup when he was a baby, resulting in a scar on Hiccup's chin, which is how Valka realizes that the dragon Rider she captured was Hiccup.
- Cloudjumper is one of the very few species of dragons, along with Toothless, who have peg-shaped teeth.