Hroar

Hroar is a young Viking in the Riders of Berk: Comics. His first appearance is in the fourth volume The Stowaway.

To put it simply, Hroar is exact opposite of Hiccup.

Personality
Hroar is a brawny Viking with an equally brawny personality. He shows a curiosity to learn more about dragons, hiding his real intentions.

The other Dragon Riders immediately take a liking to him, happy to show off their dragons. When Hiccup first explained his suspicions, the others didn't believe him, thinking he was jealous.

Hroar is the opposite of Hiccup. While Hiccup is more on the smaller side, Hroar is muscular. He also doesn't hesitate to do things, while Hiccup usually thinks things through. They also have a different effect on dragons.

Hroar appears to have in interest in Astrid, saying the two of them were kindred spirits.

The Stowaway
The Berkians discover Hroar hidden on board their ship after an encounter with the Outcasts. He introduces himself, saying he's from Knaff, one of the western isles. He explains his reason for sneaking aboard is he heard tales about Berk training dragons and had to see it for himself.

Hroar is made a guest at Hiccup's house until a trip back to Knaff can be arranged. There he meets him and Toothless, who are both not quite thrilled. When Hroar approaches Toothless, he begins to talk in a strange language that the Night Fury reacts to. Hroar claims it's a lullaby that his father would sing to him after working in the slate quarry. He then convinces Hiccup to let him meet the other riders.

At the Academy, everyone is excited to meet Hroar, including Astrid. Hiccup tells her he's not quite sure what to make of their guest but Astrid just thinks he's upset because Hroar left his home to see what else is out there, something Hiccup said he thought about the day before. Astrid then invites Hroar to ride with her on Stormfly, again making Hiccup upset.

The next day, a few of the dragons begin to act up. Stormfly gets into a fight with a Thunderdrum, Hookfang lashes out (more than usual), and even Toothless get in a skirmish with a group of Terrible Terrors. Once everything settles down, Hiccup can't help but think it's strange the dragons are acting wild as soon as Hroar arrived. Again, the rest of the riders think Hiccup is jealous of him.

When Hiccup returns home, Stoick tells him that Hroar wants to join the Dragon Academy and should get his own dragon, much to his son's dismay. The teens then head out and try to help Hroar bond with Torch, a young Typhoomerang. After being bucked a few times, Hroar manages to get the hang of it.

Later that night, Hiccup does some digging into Hroar's story. He finds that Knaff is a remote island, even more so than Berk. He also finds out there are no slate minds on Knaff, which adds to Hiccup's growing suspicions. Unknown to him, Hroar is spying on the young Viking.

The next day, Hroar convinces Astrid to take him to Dragon Island. Despite her warning him not to land, Hroar does anyway, finally revealing his true nature. He begins to chant again, and the dragons react, just like Toothless did the other day. Hroar explains it's his special talent. While Hiccup can calm dragons down, Hroar can set them off. After enraging the dragons on the island, Hroar tries to lead them to Berk, so when they destroy it, Alvin the Treacherous can finish the job.

Fortunately, Hiccup had already pieced together that Hroar snuck aboard the Berk ship during the Outcast attack. While the other take care of the wild dragons, Hiccup goes after Hroar. He unlatches Torch's saddle, causing him to fall off. Astrid catches him, though she said it was tempting to let him fall. She drops him in a fish barrel as payback.

Hroar is later left in a more neutral area for the Outcasts to pick up, at least according to Hiccup's plan.

Abilities

 * Dragon Enraging: Unlike Hiccup, Hroar can make dragons react wildly. He chants in an ancient language and does strings jesters with his hands. Hroar explains he'd not quite sure if it's the words or the jesters, or even just something about himself.

Trivia

 * Hroar is the youngest Outcast, however, it is possible that he was just allied with them and not an actual Outcast. Alvin was banished from Berk about 20 years before the first film, so that would mean Hroar was born after that. However, there have been not female Outcasts seen, so it would be impossible.
 * Hroar name might be a deviation of "roar," hinting how he can make dragons act out.
 * Hroar is similar to Heather. Both were sent by Alvin to gain an advantage over Berk, and only one of the riders didn't trust them; Astrid for Heather and Hiccup for Hroar. They are also the only teens seen that are not from Berk. Though they are quite different as well; Heather only worked for Alvin to save her parents while Hroar is an actual villain.
 * Hroar is the only person Astrid meets for the first time and was not suspicious of; and the first Hiccup was suspicisous.
 * Hroar is the first person aside from Hiccup that Astrid has shown any degree of interest in.