The further they flew, the colder it got.

Soon enough it became clear that their strategy of avoiding Feather by staying away from civilization had a price—they couldn’t descend again without buying or finding gas, and so they never did. But not landing meant they had a limited supply of food, and an even more limited supply of fuel.

The little firebox struggled to keep the cabin warm against the blasting arctic chill, except when filled almost to capacity. But they were running out of coal much too fast to burn it that way.

That meant even the cabin started to feel chilly. Summer wore her winter jacket all the time, with the scarf wrapped securely around her neck. She’d be absolutely screwed if she blew off the deck, since it would mean she couldn’t fly—but at least she wouldn’t freeze. The others had to do likewise, spending their days moving as little as possible huddled in a cramped cabin.

There was at least one little mercy—as cold as it was, they all slept in the same bed, sheltered under as many blankets as possible. With Emerald there, there was no danger of Summer’s chemistry getting the better of her common sense.

Even Summer’s electronics started protesting from the cold, and she packed them away in her insulated box, which she left near the fire at all times. If any of that stuff froze, she couldn’t exactly send it in for an RMA.

They spent as little time outside the cabin as possible, and packed in extra fabric into the window-cracks and under the doors. There was no longer water to waste on showers, and no fuel to heat.

Just when Summer was beginning to doubt the wisdom of avoiding Feather so thoroughly, as well as wondering if they shouldn’t be traveling such a direct route—Sharp announced that Sleighsburg was finally coming into view.

“We’re not actually going to land there,” he said, shutting the door closed behind him and brushing the snow from his mane. “You both remember what happened last time. I think Emerald could probably go back safely, but not us. Hopefully they don’t think it’s worth it to send an expedition out to attack us if we don’t mess with them.”

“What about taking off again?” Summer asked. “Won’t we have to vent lots of our hydrogen to land?”

Sharp looked away, ears flattening. “Well, that package from the hippogriffs is heavy. Between that and giving up one of our passengers… it should be enough. Worst case, I can lose the portable workshop, it’s heavy as buck. Can fly back up here for it once things have settled down.”

“Oh.” She rose from the kitchen table, making her way to the large windows at the front. Sure enough, she could see the strange shape of the Doorway on the horizon. A mountain, but not. Her road home. She clutched the necklace tighter, squeezing the pearl once for reassurance. Its magic was still there, entirely unaffected by the cold. Too bad she couldn’t use it to turn into a polar bear, or something with thicker insulation. “Guess it’s finally time. You ready to see another world for yourself, Sharp?”

He smiled weakly at her. “Seeing Mt. Aris was its own kind of adventure. I’d say I’m ready for another.”

“Me too!” Emerald exclaimed, shaking herself free of her nest of blankets and pillows. She was the only one who didn’t wear her jackets inside—either being a pegasus or a lifetime in the north made her less sensitive to the cold than either of them. “I’m going, Master. Don’t even try to say I can’t. It won’t work.”

“Wouldn’t dream of it,” he said, smiling ruefully. “But not yet. I need you to prepare to winterize the engine. There’s no telling how long we’re going to be gone.” He tilted his head to the side. “Summer, if our trip does go successfully, would we be able to obtain hydrogen gas on your side? Or hydrochloric acid and fine iron, if that’s available.”

“Either one,” she said. “You’re going to be… astounded, by what our machines are like, Sharp. Everything you’ve ever seen from Feather will be like cheap toys.”

“I am eager to see it,” he said, though he didn’t sound eager for much of anything. And Summer couldn’t blame him. She knew exactly what he was feeling. I don’t want this trip to end. Why does there have to be a buckin’ time limit. We could’ve made excuses to travel all over the world, see amazing things. Spent months investigating that castle, weeks more reading from the library in Mt. Aris. Maybe even met the real rulers of Equestria.

Some part of her knew that when she stepped back through the doorway, she’d be saying goodbye to everything she’d done here. No more hippogriff body, no more magical world. No more being female, for all it had been more of a frustration than a desire. No more exploring the ocean, or magic of transformation. The doorway back to Earth would take away everything she’d been given, including her friends.

I shouldn’t let them come with me. What if they don’t get changed into humans, and they end up in some zoo somewhere? Or worse, they might end up in some US government black site, the kind of thing you heard about on conspiracy channels and in bad movies. Summer hadn’t believed any of that before, but now she was a magical bird that could turn into a fish, so all bets were off.

But if I send Sharp away, then I won’t be able to explore the world with him. There was still that dream, too good to be true. She could be the one to document this side, so that no one else had to be transformed. She already had the lay of the land. Maybe Equestria would extradite Kate back to the US and make that problem go away while they were at it.

“I’m going to put us down about a quarter mile from the Doorway,” Sharp said, zipping up his jacket again. “Summer, if you’d like to join me on the deck? I’ll need you to be ready to get us nailed down. Hard enough that the Horizon doesn’t go anywhere while we’re over there.”

“Sure.” She gave Emerald a quick pat on the shoulder, then hurried after him. She was already wearing the jacket, but she grabbed her scarf from the hook and wrapped it tight before joining him out on the deck.

No wonder the engines were working so hard today—the wind seemed as determined to blow them away from Sleighsburg as it had been to get them away from Athemis. Just like last time, they were winning. “I’m taking us down gradually!” Sharp shouted. “I don’t want to lose any more gas than we need! But we can’t drift into those trees, or we might puncture the gasbag!”

She didn’t need telling what that would mean. If they lost their gas, there would be no return trip. Sleighsburg had ships visit and they could probably get one down south—but the villagers might just decide they wanted to finish what they’d started.

There were no clouds, but the fierce wind below them whipped snow off the ground, lifting it in a sheet like a knife up in their direction. Summer wanted to get a better look at the Doorway, practically expecting the sky to be open with a portal back home even now—but so far, nothing.

Summer waited on the side of the deck, with a thick rope coiled over her shoulder. Then, when they finally dropped low enough, she removed the jacket and glided down to the surface. This time she hardly even thought about it—her wings knew what to do, catching the air and taking her down without difficulty. So long as she kept her angle squarely into the wind, it couldn’t turn her around and toss her into a tree.

She landed in a snowbank, swallowing her for a moment in fluffy white. She struggled and kicked and crawled her way to the surface, taking the rope with her. There’d be no spiking this line down, no chance of getting to the bottom.

But beside her was a pine thicker than she was, with healthy green leaves and a thin layer of frost coating its bark. The perfect subject. She tossed the rope around it, working her cold claws clumsily until she got the knot secure. If I never make it back to Earth, I can still thank that Barrow job for teaching me how to tie a knot.

Unfortunately, her first-time flying was a little harder to recreate when jumping just pushed her lower into the snow. She made her way over to the edge of the ship, waving her forelegs. “I can’t fly up! Drop me a ladder!”

She couldn’t hear Sharp’s response, but a few seconds later the rope ladder came down, landing roughly in the snow in front of her. She scrambled up, breathing heavily, and beginning to feel numb from cold. “How… many more of these do we have to do?” she asked, shaking her wings to dislodge the snow.

“Two if we were staying for an hour. For us… four. You don’t have to climb back each time, though. I’ll toss them down one by one, and you can just follow the ropes.” All that time he kept his hooves on the controls, fighting with the engines and the wind with barely-suppressed desperation.

Summer bit back her frustration, turning back towards the side. “Just point me… towards the next one,” she said. “I’ll… yeah.”

It took well over an hour to get them all secure. But by the time she was done, they were tied off so thoroughly that only the gasbag moved with the wind, and even that not very much. Summer flopped onto the deck one last time, with chunks of ice melted to her body in places and her wings completely numb. But she’d done it, that was what mattered. And her body was apparently better in the cold than Sharp’s. Maybe it was a bird thing.

“I’m not sure I’m… ready to go on today,” she said, rolling onto her back and looking up at him. The engines were silent now, meaning she didn’t have to shout. Even the wind seemed to be dying down now. Of course it would, now that we’re not trying to land. Nothing’s ever easy. “Do we have to go right away?”

“Nope.” He walked past her cranking the ladder back up and flipping the railing back into place. “I didn’t think we would. We’re all kind of… awful, from traveling. I figure we splurge the rest of our water and fuel to clean up for tomorrow. Either we can get supplies from your world, or… send Emerald back to her village to buy some. Either way, we can get more after this.”

His words lifted a weight from her shoulders. The experiment wasn’t going to end overnight—and neither was her time together with the ones she’d come to care about. “Is that… safe?” She glanced over the edge again, out into the wilderness. “I heard wolves last time I was here.”

He nodded. “There are wolves, but they can’t jump twenty feet, or climb trees.” He bent down, lifting her up onto his back. For all the struggle that had been for her, he didn’t even flinch. “Let’s get you inside. You can have the first shower, how about that?”

It was fantastic was how it was. She couldn’t lay down and soak in the heat the way she wanted, but even so the steam billowing around her and the chance to use the soap wet was like waking up after a long hibernation. Might be the last time I ever do this as a bird.

While the others took their turn, she cooked the best meal she could manage with the least-unappetizing cans they had left. One last jar of apples made for a decent-enough dessert, even if they didn’t have any hot chocolate left to wash it down.

Yet by the time everypony had taken their turn and was gathered around the table, Summer found the same awkward silence returning. The Horizon wasn’t rocking back and forth in its flight anymore, instead it twitched lightly with the wind, occasionally jarring from one side to the other.

Sharp didn’t even say a word until he’d cleared away his first helping. Emerald looked between them, obviously unhappy.

Of course it would be her who finally forced them to stop being silly. “Are you ready for tomorrow, Summer? Are you really… ready to go home?”

She shifted in her chair, but Emerald didn’t let her look away. The filly was determined. “Not really,” she admitted. There was no sense lying. She’d made up her mind. “But the experiment doesn’t last forever. When they shut off the field emitters, the thing that let me cross will be gone. I can’t give up my whole life.”

“We did,” Emerald whispered.

Stunned silence. Sharp looked like he was going to reprimand her—but he just stared back into his empty plate.

Emerald had been whispering, but now she got louder. More emotional. “My mom was… she was awful.” She wiped her eyes on the back of her foreleg, soldiering bravely on anyway, scooting away from Sharp so he couldn’t comfort her. “But I didn’t… I still had to l-leave. And Master Edge left his whole workshop behind! It took him years to build, all gone. I thought you liked us. You’re nice to me, and you like Sharp… why would you want to leave?”

Summer put down her fork. The slightly-sour smelling apples didn’t really excite her anyway. “I don’t want to leave you guys,” she said. “And Equestria… your world is something amazing. I don’t really want to leave it either. That’s why this is so hard for me, Emerald.”

“You don’t have to go back in person,” Sharp suggested. His voice was low, nervous. Like each word cost him. “You could write a letter to your family, send that instead. Your possessions came through when you arrived, so the reverse must be true too. We could make something so big that your… base… would notice.”

Summer shook her head. “I love my family too much for that. If I was locked away forever, that would be one thing. But I should be able to tell them goodbye myself. But… it’s not even really my choice to make.”

She rose from the table, pacing faster and faster. It was easier now that she didn’t have the jacket inside, slowing her movements. “Our universes are connected, Sharp. Yeah, you gave up your workshop—but remember why you set it up in the first place. You wanted to learn more about the Travelers, you wanted to visit the other side.

“Why should I be the only one who gets to come here? Why should no Equestrian ever get to go to my side? When the experiment ends, that’s it—we separate. Who knows what incredible randomness would be required for us to connect again? It might never happen. But if we go over there, then we’re making two worlds come together.

“And…” The most important part. “What I’m hoping happens is that they want me to come back here. I won’t be saying goodbye, but coming back to learn more about Equestria and send pictures home. It makes sense. We’re friends, and you’ve got this airship. We might have to travel together for… months more, maybe years.” She blushed, scratching at the deck with a claw. Normally she didn’t do that, but… she was getting distracted.

“You really think they’ll do that?” Sharp asked.

She met his eyes, fighting back her own tears. She didn’t want to let herself do it, not in front of Emerald. “I don’t know. It depends how big a deal it was when I went missing in the first place. What kind of authorities we attract when we get there? It might be dangerous for you two. Probably… would be better if you didn’t, just in case.”

“Don’t even think about it.” She hadn’t seen Emerald moving. But now she ducked in beside her, wrapping a foreleg around her leg so tightly that she couldn’t get away. “We’re going, Summer. If it’s dangerous, well… we went this far. We had to get away from Feather, we crossed deadly oceans. Do you really think the Travelers on your side will be worse than all that?”

Maybe. “No,” she said. “No, of course not. And… you’ll look like me. I think? I didn’t turn into a pony over here, so I’m not quite sure how it will work. Maybe you’ll be, like… elves or something. We’ll just have to make it clear how you’re ambassadors and stuff. Once it gets out that the first real aliens are visiting… well, you guys will be famous forever. You could go on tours, get book deals and… probably things you don’t care about.”

Sharp nodded. He approached her from the other side, wrapping his forelegs around her in a hug. The same thing Emerald was still doing, though he didn’t hold on for nearly as long.

“I’d trade all of that not to give up what we’ve built together, Summer Ray. After… the things we saw, I’m nervous to try and connect our worlds together. But I trust you. And if you think that’s what we should try and do, then… I’ll help.”

Finally he broke away, crossing to the lights and turning them down. “But not tonight. We’re about to be the first ponies to cross the Doorway, we should do it while we’re still awake. Also… we’d probably freeze on the hike over right now.”

“Yeah,” Summer agreed. “Tomorrow.” Tomorrow I’m going home.