The late afternoon sun glinted off the water. Far below me, I could hear the surf crashing against the base of the sea stack. I dangled my legs over the edge, knocking my feet against the sheer rock cliff. My boot made a gentle bumping sound. My metal prosthetic attached to the other leg clanged quietly against the stone.

I sighed, pulling my leg up and looking at the prosthetic. I had long since learned to walk on it as well as my own foot. But still… it would never feel the same.

A fishing boat sailed slowly around the tip of the island, far in the distance. Berk's ships were another thing that would never be the same, at least not for many years. Even though over three years had passed since the Red Death had annihilated the fleet, we had not yet restored it to its former glory. We hadn't been overrun by our enemies, because we had our dragons. But someday, our enemies might get dragons of their own. Several had tried. And when they succeeded, we would need to be ready with every kind of weapon that they might have. And that includes ships. It would be several more years before our fleet got as great as it once was, and it would cost vast amounts of gold. My head throbbed as I thought about it.

It was all my fault. If only I had managed to warn everyone. Instead, I let them almost die.

As the years had passed, I was managing the guilt well. It only rarely bothered me, because it had all seemed to work out, now that the dragons were among us. But for the past several weeks, it had been getting to me.

I struggled to keep my eyes in focus as I stared back down at my metal leg. I probably lost my foot as punishment for my foolishness.

In frustration, I buried my face in my hands. "Why did I have to be so stupid?" I groaned. I left my people vulnerable to attack. I almost killed them, I almost killed Toothless, I almost –

Just then, Toothless rested his head on my shoulder and coo'd. He felt comforting.

"Hey, Bud," I murmured. I reached up and patted his head.

"There you are!" a shout came from above. My heart fluttered as I heard that voice.

Astrid.

She swooped down on Stormfly and jumped off. "We've been looking all over Berk for you."

"I've been here," I said, trying to make myself look bright and smiley.

"Hiccup, what's wrong?" she asked. "You've been slipping off all the time these past couple of weeks. You never talk much anymore, and you're clearly faking that smile. What's bothering you?"

"B- bothering me? Nothing's – nothing's bothering..." My voice trailed off as she knelt down and touched my hand. For a warrior strong and fierce, her hand was so soft. I turned and looked her in the eyes. I blinked my own eyes, trying to focus on hers. Blue-gray in color, they were framed by her blonde bangs. I felt like I could gaze into her eyes all day.

"Hiccup, what's wrong?" she asked.

"Wrong?" I asked. I tried to remember what we were talking about.

She smiled a little at my confusion. Her lips were soft, too, and such a pretty pink…

I looked down. It was the only way I'd be able to think.

"It's just… everything's my fault."

"Everything? What do you mean?"

"The fleet is small. We're vulnerable to enemies. All the warriors almost died fighting the Red Death."

"Hiccup… that's been bothering you all these years?"

I shook my head. "No… just the past couple of weeks."

"It all worked out," she said. "It wasn't a great situation, but we came out stronger. We would never have accepted dragons living with us if it weren't for that."

I shook my head. "It would have worked. It would have happened either way."

She stood up. "So it happened the way it did. It worked out, and we all agree that it's better now. Everything you did, you did to protect all of us. Besides, why are you thinking about this now, if you haven't all these years before?"

"I don't know. It's just… remember that time a few weeks ago, when I fell off Toothless and hit the academy's wall really hard?" She nodded, so I continued. "As I hit the wall, it all came back into my head. I haven't been able to shake it since. I messed up. I really messed up."

I shook my head, feeling a little dizzy. It must be the headache I was giving myself from looking at the sun glinting off the water. I looked back up at her, willing the butterflies in my stomach to settle down as I saw her eyes again. "So why have you been looking for me?"

"Fishlegs found something, in one of the caves. He wants you to see it."

"Well, let's go," I said, climbing onto Toothless's back. "Race you!" Toothless sprang forward into full speed. I could barely hear Astrid call, "Hey, no fair!"

Toothless and I flew and within a minute, had circled the island to where the cliffs were. We slowed down, waiting for Astrid to catch up. A Nadder is fast, but can't quite compare to a Night Fury.

As Astrid approached, I called, "So which cave is it?"

"Follow me," she responded. She and Stormfly spiraled down to a cave halfway up a cliff in the forest.

We followed her down and Toothless landed gently, as if he knew I had a headache. "Thanks, Bud," I whispered.

I followed Astrid into the cave. It was pitch black inside. "Hey, Toothless, give us some light?" I asked.

Toothless let out a weak plasma blast which lit a lantern I pulled out of his saddlebag.

Astrid led us around a few corners. The temperature started getting a little cooler, although not much – even now, in midsummer, Berk didn't get very hot. After a few minutes of walking, we came to Fishlegs, Snotlout, and the twins gathered around a part of the cave wall. There was a narrow gap in the floor right next to them; it was so small, I doubted that most people could fit through.

"What's up, Fishlegs?" I asked, walking over to them.

"Check this out, Hiccup," Fishlegs said excitedly. "These are some ancient runes here, probably from before people first permanently settled on Berk. This is the historical find of the decade! This is astounding! This is –"

"Boring!" yawned Snotlout. "At least until you tell us what it says!"

"May I?" I asked. Fishlegs nodded and moved to the side so I could get a closer look.

I knelt down so I could see closer. The runes looked a little blurry. It must have been the dim light. I couldn't quite make them out.

"It's an old form of the language," Fishlegs explained. "I think I've been able to translate them."

"Well, what does it say?"

Fishlegs, not wanting to risk touching the stone with his hands, used a sword's tip to trace the shapes of the runes as he read the ancient words, "'The history of our actions need not be our fate. We can overcome it. On this remote isle we have found they key – the key to changing the past.'" My jaw dropped as he continued. "'Through this narrow tunnel lies the door to the past. Slide through it… and change your fate.'"

"The door… to the past?" I asked. "How is that possible?"

"I don't know," shrugged Tuffnut. "But those doors are kinda sly, always sneaking up on you."

We all stared at Tuffnut for a few seconds. Then Fishlegs answered, "I don't think it is, Hiccup. It sounds like some of our legends, an old wives' tale."

"That could be..." I mused, my voice trailing off.

A loud rumble came from somewhere in the cave. Astrid grabbed her ax, ready to fight. Snotlout stood at the ready as he grabbed his knife.

"Sorry, just my stomach," Tuffnut laughed.

"Yeah, his stomach always does that at dinnertime," Ruffnut explained.

"Dinner? Sounds good," Snotlout said.

"Is it that time already?" Fishlegs asked. "Where has the day gone?"

"My parents will be worried if I'm not back soon," Astrid said. "I've got to go."

"Me, too," Fishlegs said. He shivered. "I don't want to be caught outside after dark. Things happen after dark."

I stayed where I was. "You guys go ahead. I'll catch up later."

Astrid hesitated. The darkness still made it hard to see clearly, but I could see her worried expression. "Hiccup… are you sure?"

"Yeah, I'll be- I'll be fine. Don't worry about me."

"I wouldn't think of doing anything," Fishlegs warned, handing me the sword. "There's no evidence that the thing's real, no evidence that it's safe, and no evidence that it would make things even better. We don't even know if it would bring you back in your current form, or back as you were, or if you would remember things or forget them."

"So..." I figured, "you're saying that if someone went back through that – hypothetically, of course – they might not remember that time had passed?"

"No. Because time wouldn't have passed."

"Hmm. Interesting."

"You're not going to try anything stupid, are you?" Astrid asked.

"Me? Stupid?" I asked nervously. "Nah, I'll just- I'll just study these runes for a little while. Then I'll catch up with you."

"Well… alright," she agreed reluctantly. "Just send Terror mail if you need anything."

"You know I will!" I assured her, waving as they left.

I looked back at the runes, tracing their shapes gently with the sword, and listened until I was sure they had left the cave. My head pounded as I thought hard about a plan.

I might not remember… how could I make sure history was shifted? So I wouldn't have put anyone in danger… so I wouldn't have wrecked most of the fleet… so I wouldn't have lost my leg?

I might not remember… I might not know to change things. How could I make sure I did?

No. No, I couldn't do this. Astrid was right; it all worked out.

The runes looked more and more blurry. I shook my head to try to clear my vision. All it did was make me dizzy. I turned and stepped toward Toothless. I pulled my canteen from the saddlebag, taking a slow sip of water. That felt nice.

Still holding the canteen, I started pacing the rough cave floor, at war with myself. I couldn't do this, I couldn't –

My metal leg slipped into a crack in the rocks. My leg twisted around, making me fall to the ground. As the canteen flew from my hands and spilled, I heard something snap in the prosthetic.

"Great," I groaned. I pulled my leg toward me and inspected it. The bottom had broken, so I could barely walk and certainly couldn't fly on Toothless.

Toothless came over to me, making sure I wasn't hurt.

"I'm fine, Bud," I said. I rifled through his saddlebags, but I didn't have any spare prosthetics with me. Apparently, that was my spare. In resignation, I pushed the empty canteen back into the bag.

"Here, help me up," I said. Toothless used his head to push me up. I limped over to the nearest wall, the wall by the tunnel, using it to lean against.

Pulling out my notebook, I tore out a page. I wrote a quick note explaining my circumstances.

I let out a Terror call. A moment later, several Terrible Terrors flew toward me. I recognized one; it lived outside my house. It would fly back there and my dad would see the message.

My eyes blurred. That made it hard to fasten the knot holding the note to the Terror's leg. Frustrated, I leaned forward to see it closer.

My head started to spin even more. As I leaned forward, I lost my balance. I stepped forward frantically, trying to keep my balance. My metal leg hit the ground, but didn't balance me at all because it was broken. Still clutching the Terrible Terror, I fell to the side and tumbled down… down to the Door to the Past.