Villains Scare Hiccup- but not enough!

What makes a character scary?

Seeing traits you are proud of in a villain

Hiccup had never met another person as smart as himself before. That wasn't surprising, really, having grown up in a small viking village. Nor was it truly surprising that there were other smart people out there. Not something he often thought about, but not surprising. Sometimes he thought about how refreshing it would be to have a discussion with someone more like himself. He had never considered what he would do if confronted by an intelligent villain.

Hiccup could fight- Hiccup had fought- Ryker. He was afraid, but he did it. He knew that he could outsmart him, he knew that he could get away, he even understood how relying on brute strength to survive in the harsh North could lead a person like Ryker to believe the things he did. But Viggo. Viggo was always a step ahead of Hiccup. Any plan Hiccup made, Viggo had prepared for, every chance Hiccup saw, Viggo saw first, every ploy Hiccup tried, Viggo could counter!

Hiccup's intelligence had served him well over the years, more than making up for his lack of the typical 'Viking' build. But Viggo was just playing with him, like he was no better than- than one of Alvin's most dimwitted guards! Hiccup was scared. He had never been this scared. Not when St- his father yelled at him, not during raids, not trying to prove the entire 'Viking way" wrong, not even facing down the Red Death did Hiccup feel this scared.

Scared for himself, yes. But also -more,- for those he cared about, and the principles he stood for- the truths he held dear. He was afraid for the other Riders, because he couldn't keep them safe anymore. He was afraid for the Dragons, for the peace he sought so desperately to build. He was afraid for his entire world, because he couldn't fight for and defend them anymore.

He could try. He would try. He would fight to the ends of the earth and the end of time itself. But no matter how hard he fought, how hard he tried, it wouldn't be enough. It wouldn't be enough because he could not beat Viggo, because Viggo was smarter than Hiccup. And that scared Hiccup. That scared him a lot.

An apparent lack of humanity or morality.

Stoick was scary. Ryker was scary. Viggo was terrifying. Johann, though. Johann was even worse. Viggo, at least, had a sense of honour. His values didn't always -or ever- align with Hiccup's, but he had them. There were lines he would not cross, there were codes he would abide. Hiccup was scared -terrified, even- of Viggo, but at least he knew how to face him. Johann had none of these restraints.

Johann would commit any atrocity, and enjoy it, if it helped him achieve his goal. Johann didn't care who he hurt, or what consequences his actions might have: he was as brutal to his grudging allies as he was to his fervent enemies. Hiccup struggled to fight Johann because he couldn't face him. Not on any kind of balanced field. Johann didn't have to outsmart Hiccup, not like Viggo had. He just had to do things so deplorable that Hiccup would never imagine even a villain being capable of. And he did.
Because of this, while Hiccup didn't fear Johann, not like he did Viggo, or Ryker, or his father, Hiccup did fear what Johann would do, more than he feared anyone else.

Knowing that they believe in their cause more than you do in yours, and that they will do whatever it takes, even when you would turn back.

Drago scared Hiccup. Viggo and Johann were scary, but they were businessmen. They didn't fight for a cause, they didn't fight for principles or for truth, not like Hiccup did. They fought for money. Drago had a cause. An insane, perverted, evil cause, but still a cause. And Drago believed in his cause, just like Hiccup did. He truly believed that he was doing the right thing, that he was making the world a better place. He believed that his cause was just, and his actions glorious.

Because of this, he fought with valour, with passion. He fought each battle as if his life depended on it, as if his heart beat in time with his victories. And his fervor was not spent in vain. Drago had an army. A massive army of men and dragons. He had even brought a mighty Alpha to heel, all in pursuit of his vision, a vision that was becoming a reality.

Hiccup did not think he could claim the same. He was barely managing to maintain what he had, much less go off crusading to spread his vision to the world. He believed in his cause, and he fought for it. But Drago... Drago shook the world itself until he was given what he wanted. What was Hiccup supposed to do in the face of such conviction? He knew he was right, or at least, not wrong... But maybe... could Drago also be right? How else could he fight on as he did? What made Hiccup right and Drago wrong, besides Hiccup's saying so?

Yes. Drago scared Hiccup. More, even, than Viggo or Johann, because Drago made Hiccup doubt himself. He made Hiccup doubt himself, his capabilities, his achievements, even his cause. Everything Hiccup held dear, everything Hiccup had fought and worked and sacrificed for, everything Hiccup believed in, had dedicated his entire life towards, Drago challenged. And that made Hiccup very, very scared.