So, this chapter explores what Hiccup can do in finer detail. Soon, the action and adventure will start ;) but every hero needs their backstory! hope you enjoy!

Hiccup was in shock, complete and utter shock, over what his body had become.

He'd spent the entire afternoon in the training arena, pushing and testing himself. Not everyone stayed the whole time. They would wander in and out, occasionally leaving to various parts of complex Hiccup had yet to see. The only person to stay indefinitely was Astrid.

Whether it was because she feared what he would do if she left him alone or that she actually wanted to be there, Hiccup didn't know. Sometime she would help, guiding him and providing advice. Other times, Astrid would stand quietly off to the side. Hiccup often forgot she was there, until she felt the need to help.

Now, in what Hiccup guessed to be late that evening, they were all back. He didn't even try to hide his ecstatic, goofy grin. Not only had they'd discovered Hiccup's strength improved, but he could also run for ages before tiring. Astrid measured he went around the arena for six miles before the first beads of sweat appeared on his forehead.

However, the one that got Hiccup really excited, nearly as much as when he found he could carry seven hundred pounds, was the one he didn't quite understand. When Wiz mentioned Hiccup had powerful reflectors in his eyes, he was uneasy about what that meant. It wasn't until Ruff climbed one of Jack's snowbanks and touched the lights that he knew.

The lights flickered out, covering the arena a thick, black blanket, but Hiccup could still see.

It wasn't clear. Most of the images were fuzzy, but he could still spot Astrid's form leaning against the wall on the other side of the arena before Ruff returned the lights.

Astrid didn't let him linger in his euphoria for too long. She was eager to move one, to see what Hiccup was really capable of.

That's why he was once again standing in front of everyone, nervous as hell, but excited.

"I don't know to do it," he said for what seemed like the hundredth time. "I don't know how to switch it on and off."

"No one does at first," Jack answered, but stayed back in the group. No one was standing too close to Hiccup.

"You have to remember what set you off," Astrid explained. "I know it sucks, but we all had traumatic experiences that activated us. Pay attention to how your body feels while you phase, what it does. Then, you should be able to do it without being upset."

Hiccup nodded, but still eyed the group anxiously.

"What if it goes wrong?"

"Don't worry," Tank sneered, flexing his arms. "You won't do any damage here."

Still unconvinced, Hiccup tried to focus. It was hard to imagine it'd only been this morning that he'd been half-asleep and walking back to his crappy apartment. He could see it all; the abandoned warehouse he stopped in front as his cell phone vibrated furiously in his pocket; his stomach clenching when he saw 'DAD' flashing across the screen; his stunned hands dropping the phone as his father's words echoed in his head…

The pain hit Hiccup like a ton of bricks. For a split second, it was only mental, but the combination of grief and anger pulsing through his veins quickly fueled a fire inside of him. His spine grew hot, hotter than any burn Hiccup could possibly imagine.

In the morning, this was when he lost himself. It was the moment when he couldn't tell if he, or the thing inside of him, was in charge of his mind.

He was thankful that wasn't the case this time. He could still think.

Hiccup gripped the sides of his head and took a stumbling step backwards as another flash of heat traveled the length of his spine. It shot through his ribs, his legs, his arms…everything was heat and fire. The burning sensation consumed him like a wildfire to a forest.

Jack made to step towards him, an outstretched hand in front of him, but Hiccup stumbled backwards a second time.

"Get back!" The voice, the menacing growl, which erupted from his clenched teeth was the last thing Hiccup's human body accomplished, before he exploded.

It happened much quicker than the first time. Hiccup dropped to his hands and knees as the heat became too much for him to handle. His muscles were screaming, ripping and his bones knocked out of place. With his eyes squeezed shut in pain, Hiccup clenched his fingers against the cement, but was met with a sound of cracking stone. Fabric tore around him and his shoulder blades sliced through his back. Hiccup couldn't hold bit back any longer. He let out a yell of pain, but instead heard something much deeper and darker.

A roar.

Hiccup's teeth cut into his lip and a metallic taste filled his mouth. His limbs stretched and grew. Something heavy, like a wet blanket, flapped on either side of him.

Then suddenly, after what seemed like hours, but was truly only a few seconds, the heat stopped. The agonizing ache in his muscles ceased and his bones didn't feel out of place. Hesitantly, he finally managed to open his eyes.

Where his hands were supposed to be were large, black claws, five times the size of what they should be. They had managed to dig themselves into the stone underneath below him. His arms, at least he thought they were his arms, had grown tremendously in width and covered themselves with black scales that matched the claws.

Looking up, he'd realized he hadn't grown much in height. His head was only a couple feet higher up than it had been before, but his neck felt funny. Stretching it out, he twisted his head in discomfort.

The faces in front of him were priceless. The twins were open mouthed, Snotlout looked ready to start attacking him, Wiz was watching from the railing in disbelief, and Jack had slightly sidestepped in front of Punzie. Astrid, however, took a step closer.

"Hiccup?" she asked, quietly. His eyes didn't miss the small movement her hand made to her hip. "You still in there?"

He tried to answer, to respond with an excited 'yes!', but instead a weird, light clicking noise came from his throat. He settled for nodding vigorously.

The smile that erupted on her face was mesmerizing. Astrid immediately approached him. The top of her head couldn't even begin to scrape the bottom of his chin, but she went eagerly to his side and rubbed her hand down the length of his neck.

He tried to return her smile, but it felt awkward.

"Aw," Punzie squealed, pushing past Jack. "He's like a puppy!"

"Here that Hiccup?" Jack laughed, joining Punzie as she skipped by Hiccup's side. "You're a puppy now. Very ferocious."

Hiccup narrowed his eyes in annoyance and snorted, but was surprised as a puff of black smoke came through his nostrils.

"What are you?" Astrid asked, mainly talking to herself. He felt something pull on his back and twisted his head to see what she grabbed.

Jumping in surprise, he nearly knocked over his three companions as he finally saw the rest of him.

Astrid had grabbed one of his two, large leathery wings that sat on either side of back, but that wasn't nearly as surprising as the long, black tail that swung out behind him making nearly thirty feet long. His legs matched his arms in both thickness and in the claws that protruded from the edges. Every inch of him was blacker than midnight and covered in scales.

"If you breathe fire I am going to lose my mind," Ruff declared and her brother nodded in agreement.

"Alright so he looks cool," Snotlout said, rolling his eyes. "Big deal."

"You're probably element proof," Astrid commented, ignoring Snotlout. Her hand was still skimming over his side, her nails lightly scraping the scales and testing them. Her small smile of amazement seemed to glow. "And I would bet money that those talons can cut through steel."

"And you can fly!" Punize laughed. She reached up and stroked her hand down Hiccup's jawbone. He was surprised at how long it was. Opening his mouth, Hiccup realized how large it had become. His tongue flopped out, scrapping against his pointed teeth.

Astrid had wandered back up to his head now. The top of her head was a few feet below him, but she tilted her neck, smiling. The blonde bangs fell from in front of her eyes and Hiccup could see the bright blue in them sparkling.

"You really are something," she muttered, patting the black scales on his neck.

Being a giant reptile was pretty awesome.

It was figuring out how not to be one that proved difficult. It was several hours before Hiccup managed to turn back to his normal, lanky, twenty year old self. Everyone, but Astrid, eventually wandered off to their rooms for the night before he figured it out.

Astrid had turned away from his naked body and thrusted a pair a sweatpants into hands that he eagerly hurried into.

"Thanks," he mumbled, quickly sliding them onto his hips as she turned around. "Dang. I liked those shoes."

He looked at the shreds of fabric and remains of his sneakers spread across the floor.

"Don't worry," Astrid laughed, heading towards exit. Hiccup quickly followed. "Tomorrow you'll be able to pick through your possessions and decide what you want to keep. That includes clothes."

"My possessions?" he asked, as the two entered the dimly lit hallway. "Where's all my stuff?"

The hallway was eerily quiet. The only sounds were the tapping of Astrid's boots and the soft padding of Hiccup's bare feet.

"The C.I.A. has it all," she responded. "Or, at least, one department of it does. They confiscated everything, made a story of why you left your job and apartment, handled any confused family or friends…all that stuff. We'll head there tomorrow so you can get all your stuff and fake identity."

"We get to leave?" Somehow he'd gotten it stuck in his head that they'd always be underground, unless their heroism was needed.

Astrid soft laugh echoed down the walkway. "We aren't prisoners. We can go anywhere we want. The only reason we live underground so it isn't easy for others to find us."

They walked in silence. Hiccup tried to remember what staircases they were going up and what turns they were taking. It was going to take forever for him to memorize the layout.

"When do I get a superhero name?" he asked. "And a suit?"

"You pick it. It needs to be before our next call so we can tell the public. As for your suit," she smiled up at him. "Wiz has been working on it since he scanned you this morning. It's more difficult than you think. They're all bio suits. They've got living replicas of our cells in them so they can match what we do."

"So, mine will change with me? I won't be naked each time I change back?"

"In theory."

Hiccup finally recognized where they were. If he was correct, Wiz's lab was around the corner and the front room he'd entered through earlier was in front of them. Astrid turned and led him to a hallway with several doorways and no windows to see inside the rooms. She suddenly stopped in front of the closest one and Hiccup stumbled to avoid running into her.

"This is your room," she said, turning to look up at him. "Punz is at the end, Jack is couple down, Snotlout and the twins are around the corner, and I'm right across the hall. The showers are down there. I asked Jack to put your backpack in your room already. Get some sleep. You'll have another busy day tomorrow."

Astrid started to go across the hall, but froze when her hand touched the doorknob.

"Hiccup?"

"Hm?"

"Um, I'm sorry." Her eyebrows knotted together in genuine concern and Hiccup frowned.

"About what?"

"About being harsh to you. We've had problems with new people before. I was just looking out for my friends."

"I know," Hiccup smiled. "Don't worry about."

One corner of her mouth turned up, before she disappeared into her room.

Hiccup copied her and flipped on the light as he walked in. His new bedroom was bigger than his old one, but not by much. There was a double bed with plain, black sheets, some bedside tables, a lamp, and a dresser. There were several hooks aligned on the wall and it took Hiccup a moment to realize they were for his super suit.

He went and grabbed a t-shirt from his bag and shrugged it on, before collapsing on top of the covers. Hiccup was asleep before his head hit the pillow.

If you didn't get it from the description, Hiccup basically turns into Toothless. Let me know what you all thought :) i love hearing all of your opinions!