A/n: A bit of an idea from guest.

"What're you working on now?" Astrid asked, watching Hiccup attempt to pick up a hammer. She laughed slightly at his efforts; it always surprised her that, after spending so much time working with the tools in the forge, he still couldn't lift them properly.

"I was just clearing up after Gobber."

Well, that explained the hammer, at least. "What were you working on before? Adjustments to Toothless's tail?"

Hiccup nodded, retreating further into the forge to grab his work. "Ta da!" he said triumphantly, lifting it up to show her.

"I... see..." Astrid didn't see. Nothing's changed...

"It's a new feature I've been working on," Hiccup explained. In all honesty, he hadn't expected her to notice the subtle changes, "It lets me switch between me controlling the tail and Toothless controlling it. Pretty handy, huh?"

"Yeah," Astrid agreed. "But... doesn't Toothless kinda... hate that tail?"

"Oh, sure," Hiccup confirmed, "But I'm sure he'll warm up to the idea. It isn't the tail he hates, after all; it's flying without me!"

"If you're sure..." Astrid said sceptically.

'Oh, come on!' Hiccup pleaded. 'It'll mean that you can catch me if I fall...' he said enticingly.

Toothless shook his head steadfastly. 'Or, you could just not fall.' he said, but Hiccup could tell that he was cracking.

'It'll help you with our alpha duties...'

'Fine!' Toothless snapped, holding his tail down so that Hiccup could reattach the tailfin.

Hiccup smiled. He knew that Toothless was going to give in eventually. 'I knew you'd see things my way,' he told the irritated dragon conversationally, 'I even made it so that you control who's controlling the fin.'

Toothless smirked. 'Great. Let's try it!'

"Woo!" Hiccup yelled, soaring through the sky in a way he'd never been able to experience before - at least, not on the back of a night fury.

'Yes, very impressive.' Toothless rolled his eyes, highly tempted to do a roll in the air and knock Hiccup off his back.

As Toothless was in control of the prosthetic tail at the moment, Hiccup didn't need to be sat in the same position all the time while switching gears. This meant that he had the freedom to do some of the things that other riders did, like surfing.

"This is amazing!" Hiccup shouted, pumping his fists as Toothless went in for a dive.

'Yes, I can imagine,' Toothless responded sarcastically. 'Do you want me to drop you?'

'Fine, spoilsport.' Hiccup whined, sitting back down. He rested his head against Toothless's, laying back to look at the clouds as they went by.

'Hey, Hiccup?' Toothless said, a mischievous glint entering his eyes that Hiccup didn't notice.

'Yeah?'

'Think fast!'

Suddenly, the two were falling. "What did you do?" Hiccup screeched, grappling madly for Toothless's saddle.

'I switched the controls.' Toothless informed him smugly. Hiccup would've sighed at the dragon's antics had he not been falling several hundred feet to his certain doom. Instead, he clicked his own prosthetic into place just in time to prevent the two from becoming a dragon-Viking pancake and flew back over the sea again.

"Bad dragon!" he scolded, wagging his finger at a laughing Toothless, "You could've killed us!"

Toothless frowned in mock hurt. 'Do you not trust me to catch you?' he asked innocently.

'Gods, you useless reptile...' Hiccup muttered, shaking his head as he allowed Toothless to regain control of the tailfin. 'And no surprises this time!'

I may or may not have taken the 'surprise' bit a bit literally...