「It's the Republic's duty to protect this continent, this world」—— The invigorating knight declared about her country. From the archipelago at the North of the equator to the icy lands at the South, the Republic protects the entirety of the South American continent. On the other hand, they also must spare soldiers to protect the 「Huaca Tunnel」 which leads to the core of the planet. Thus, the frontiers are guarded by battalions like hers who take turns from their front lines duties—— 「However geographically speaking, there are very little threats at the frontiers of the Republic. This mission is like a half sightseeing trip.」 According to Captain Shakespeare and other knights, it's impossible to cross the oceans of this world unless it's done via submarine. There are always waves of over 100 meters in the middle of the ocean—— For comparison, in the world the young Valkyries come from, there are at most waves of 20 to 30 meters caused by natural phenomenon such as tsunamis and typhoons. This world still holds many secrets... but the top priority of the Valkyries is to obtain information regarding the Ether Anchor. ...And while they're at it, find the remaining gems to complete the Holy Sword. Oh, so that machine over there is your 「submarine」? Yeah. My wonderful 「Caledonia」 has sailed over 20.000 leagues.

注：

里格（英语：League；法语：Lieue；西班牙语：Legua，又译“莱瓜”）是源自古罗马的一种长度单位，在英语世界通常定义为3英里或3海里，在法语世界相当于10000至14000法尺不等。

p.s. 儒勒·凡尔纳的《海底两万里》（Vingt Mille Lieues Sous Les Mers）在标题中使用的就是这个单位。

 Can you cross the Atlantic in one day with it? What, does our dear knight want to go on a vacation to Egypt? I'll happily take you anywhere, as long as there is anything of value in it for me. Oh, it's not like that... I was thinking if your submarine is fast enough I could show you the way to the 「Huaca Tunnel」 myself. ...Are you serious? Isn't it the most important fortress in your country? Ahaha... We have an 「unseen enemy」 in common so I thought it'd be better if we get to know each other. But in that case... wouldn't you prefer if we showed to you what we're capable of? Hehe, it would be rude towards you guys. You're guests in my country. Besides, the speed of the 「Caledonia」 could prove to be a powerful asset. Heh... seems I'm being underestimated. I can take on Honkai beasts with my bare hands, you know! ...「Honkai」? How do you know that name? Ah, did I forget to tell you? In my world, a 「Valkyrie」 is a soldier who fights the 「Honkai」! We've come from... ummm, something similar to a 「Parallel World」. Ah, yes... I figured it was something like that... Then if I understood correctly, the 「Honkai」 is not a phenomenon unique to this world. In that case—— Please allow me to accompany you! Hey—— Why did you kneel all of the sudden!? The 「Honkai」 not only gives birth to monsters but it also corrupts the body. Without enough resistance a person can't last a week fighting in the front lines even if they were to use a thick armor. ——That's why our troops on the front lines are on a constant rotation. And when it comes to actual combat—— Only 「Star Whisperers」 who bear the name of 「Inca」 like me can fight—— It's not a place for regular soldiers. If Valkyries are on par or stronger than our 「Star Whisperers」 and specialize in dealing with Honkai beasts... Then please, let me introduce you to the Chairwoman of the Republic and the Commander of the Fortress! I beg you! I-I don't mind paying them a visit so please stand up! I can tell how important this is to you! Well, once you come aboard my ship you're already a friend. Please tell me the coordinates of our destination. T-Thanks. The coordinates are 1.5 degrees West longitude and 47.5 degrees South latitude. 1.5 degrees? Isn't it supposed to be South America? Are you sure it isn't 71.5 degrees? N-No, I'm sure it's 1.5 degrees. That's strange... there is no land on those coordinates, it's in the middle of the ocean. I see... Excuse me, Rowland-san, but which 「prime meridian」 do you use? 「Which」? Isn't the only one the line that passes through the city of Cusco? Huh? It appears the latitude and longitude system of her country is different than ours, Captain. ...Didn't expect that. Never heard of a system that didn't use Greenwich as its prime meridian. Ahahaha... I don't know where this 「Greenwich」 place is...

注：

“本初子午线”即0度经线，其东西两边分别定为东经和西经（它们再于180度相遇）。不像纬度起点（即赤道）由地球自转轴决定，理论上任何一条经线均可定为本初子午线；历史上也确实曾对此线有过不同的定义。

格林威治（Greenwich）在15、16世纪曾是英国王宫所在地。1675年，这里设立了“皇家天文台”；1884年，国际会议正式确认格林威治天文台所处的经线为本初子午线，“格林威治时间”在英国之外开始普及；1967年，国际天文学联合会正式推出以格林威治时间为参考的“协调世界时”，作为全世界的时间基准。

 Hmm. Now that we know what's the problem we can solve it easily. Are you there, Alice? Please calculate 1.5 degrees West of Cusco to our system. Understood! Based on the data from the Great Library your destination is at 73.5 degrees West longitude! ...Wow, is this a video call? In the Republic only the most important people can do them! Awesome, isn't it? Yes! It's the first time I see one being used outside of the fortress! You guys are the best reinforcements we could ask for! Cough. Major General Rowland, that's enough flattery. Ahaha, I'm sorry! Wait. Chief Buonarroti? Why are you in contact with them!? Err... what do you mean? What, you two know each other? Roland, please tell them my position in the Republic. Y-Yes. Buonarroti is the Chief of the Republic's Technology Intelligence Agency. She makes her way into many research facilities around the world and brings their technology to your country. ...Basically, you're a spy? Thank you for your praise, Ataegina. The Great Library, Alexandria's harbor, the rocket launch site at the Pyramid—— Those places are second to none in the world. I need to take advantage of them for the sake of the world. B-But... you're the 「Mayor」 now! Don't you have a duty to serve your people first and foremost!? The public's safety is in my best interest. As you know, a world at war with the 「Honkai Empire」 is far from safe. ...Besides, President Shelley is here to keep an eye on me. ..... That's right. That said, I didn't expect that secret to come out right now... But you're still in a position of power. Have your wires crossed? How can you reveal something like that so casually... ...As soon as that 「wall」 is out of the way I'll have you resign immediately. Regardless of your motives, what you're doing is against the law. Fine by me. When the times comes I'll step down myself and leave Alexandria for good. I trust you have no objections? ..... Come on, Shelley has it hard enough already, don't make things worse for her. Anyway, Curator——I mean, Chief—— This means the actions of the 「Caledonia」 are being monitored by the Republic, correct? ...If the Chairman and me are in a position to represent the Republic, then the answer is yes. I'm aware of all of your actions. I can assure you we've taken the necessary steps to ensure no one else knows about you. ——Also, Major General Rowland didn't come in contact with you under any orders. Treat her kindly, would you? Ahahaha, as if I could be mean to a cute girl like Rowland! Anyway, now that you're here might as well get you to explain a few things. What exactly is the 「Huaca Tunnel」? Does it really go through the Earth? How? Yes, it does. As for the how... Before I get to that, we need to discuss the 「Spherical Earth Theory」 first. ...Unexpected. Intuitively, we have enough ways to prove the Earth is not flat. Navigators of old came up with the idea of a 「Celestial Sphere」 by looking at the difference between the stars at the North and South, and based on the parallel relationship between the sky and the ground, they concluded the 「Earth」 was a 「sphere」. However, this reasoning isn't very tight... Because 「not flat」 doesn't mean 「it's a sphere」. People who lived during the Age of Discovery knew two things: 「the stars are spinning」 and 「the sky and the ground are parallel to each other」. From the former one can deduce there is a 「relative movement between the sky and the ground, but the latter doesn't prove 「the sky and the ground have the same structure」. The reason for that is very simple: They hadn't traveled around the whole world yet. Everyone thought the 「Earth」 had a simple structure. But it's possible there might have been places navigators can't reach where the Earth is folded or bent. The stars at night also might not be an accurate measure of latitude and longitude due to the fierce waves on the sea. That's a ridiculous idea. I mean, would it even be possible for a naturally formed Earth to have such a complex structure? A sphere is the most stable structure of all. That's wrong Captain, what the Chief is probably trying to say is—— ——The world we live in right now is not necessarily a natural formation. ..... Professor Schrodinger is right, Captain Shakespeare. This world was originally made in the opposite direction of the 「Ether Anchor」—— It's an artificial construct. Let's remember how a world map is made. The world is large, so different cartographers were put in charge of different sectors. And of course, from a ground perspective the 「surface」 is not a flat. Which means those people needed to establish clear rules. If the sectors drawn by two different cartographers overlap, the parts in common must be drawn under the same rules. And then, when all pieces are put together they become a map. ——Now try to imagine the world we live in as that map. The immense waves on the sea are the edges of the paper, and the 「high-speed currents」 you guys take advantage of are its fibers. Or perhaps it would be better to call them a 「wormhole」. The 「Huaca Tunnel」 is a 「suture」 that goes through the center of the Earth, acting as the glue and spine of a book. Thus, strictly speaking, rather than 「the Huaca Tunnel goes through the Earth」, it would be correct to say 「the Earth is being held together by the Huaca Tunnel」. ——Also, both the so-called 「spine」 and 「pages」 of this book were a product of 「someone's will」. ...I have a question. Speak. Creating a world from nothing inside the Sea of Quanta would require an immeasurable amount of energy. Even if somehow the 「unnecessary parts」 are 「folded」, it would still require vast amounts of energy. I'd like to know who made this possible and what were they after? To be honest, I can only guess what their motives were. However, I can at least be sure who that 「someone」 is thanks to the records found in the Great Library. "asatela bahidalaki jhyurhi-kavina"—— ——Perhaps you know what these esoteric words mean, Professor Schrodinger? ..... Could it mean 「ⵀⵤⴺⵚⴽ ⴳⴶⴱⴹⴽⴸⴱ ⵥⵛⵌⴱ-ⴸⵖⴱⵎ」? Yes. I see you're familiar with their language as well. ...Yes, I had a few encounters with it in the past. What are you talking about? Is it some sort of code? Hehe... You're not entirely wrong. The closest words in our language make for a very poetic name—— ——The "Moonlight throne",「Selene」. ...! ...Judging from your reaction it seems you know about it, Rita. Mind telling us what you know? ..... As far as I know, the 「Selene」 is an anti-Honkai weapon of mass destruction, and the main weapon of the mobile combat weapon 「Arahato」. ...Which is under the control of the 「Enforcers」 named 「Tesla」 and 「Einstein」. ...I see, so that's the story Schicksal is telling. 「Anti-Entropy」 and 「Arahato」... hehehe. They sure came up with a bunch of cool names. ...That said, 「Enforcer」 is pretty lame. Must have been Einstein's idea, sounds like something that big oaf would come up with. ...? It's nothing, I was just reminiscing about the past. Let's get back on track. Strictly speaking, the 「Selene」 is not a weapon. It's just an energy conversion device that turns Honkai energy into regular energy that can be manipulated. The previous civilization managed to create such technology, but by then it was already too late. Had they managed to keep their pace of development for 10 more years, the mass produced 「Selene」 should have been able to absorb Honkai energy on a world wide scale. The one called 「ⵀⵤⴺⵚⴽ ⴳⴶⴱⴹⴽⴸⴱ ⵥⵛⵌⴱ-ⴸⵖⴱⵎ」—— Was a prototype made 50.000 years ago. Then tell me, 「Mayor」 or 「Chief」—— What relationship does 「ⵀⵤⴺⵚⴽ ⴳⴶⴱⴹⴽⴸⴱ ⵥⵛⵌⴱ-ⴸⵖⴱⵎ」 has with the 「Huaca Tunnel」? 「Huaca Tunnel」 is just an alias. In the civilization we spoke of previously it was called 「ⵚⴺⵚⵇ ⵛⴺⵋⴱ」 (etera jutashi), which means 「Ether Anchor」 in our language. Then that tunnel that goes through the Earth... is the 「Ether Anchor」 itself? Correct. It seems that previous civilization had technology capable of making a 「microcosm」—— According to my sources, the birth of this world was made possible thanks to an artificial expansion caused by the 「Ether Anchor」. And that is also the fundamental reason as to why this world is stuck in the state of 「universe」. That crucial energy source—— Came from a prototype of similar nature to the 「Selene」? That used to be the case at first, yes. After the 「stream」 of the 「membrane」 stabilized around the 「Ether Anchor」, it began to grow by absorbing the Honkai energy that universes nearby leaked. The pyramids, the shape of the continents, the starry night sky—— That's how all of it was 「born」. Wait... doesn't that mean its real purpose wasn't to make 「small universes」, but rather it's a way to transform Honkai energy? Could it be its true purpose was to exist as a 「space waste treatment plant」? That's probably the case. That said—— The volume of this world is significantly smaller than the volume of the original world. Maybe if I explain it like this it'll be easier to understand. Upon activation, if one were to rank the Honkai energy used by the 「Ether Anchor」 to build a 「microcosm」, you would get a similar amount to the energy levels the 「First Herrscher」 or 「2nd Herrscher」 possessed. I see. But in terms of scale, the Honkai energy later Herrscher are able to manipulate is far higher than that... Indeed. I suspect this project was a failure for them. That failure gave us this strange, beautiful world, and at the same time it planted the seeds of calamity. And the one who would bring that calamity forth is probably the Emperor the legends speak of: 「Napoleon」. However... more often than not, reality is far different from legends. Explain them what we know about our enemy, Rowland. A never ending war has taken place in this world since the day the Republic was founded. We have our own technology and 「Star Whisperers」 while the enemy has Honkai beasts and excellent battle tactics. They're able to swiftly assemble hundreds if not thousands of Honkai beasts, discern their target and carry out their attack. And every time we develop a new weapon, it doesn't take long for the enemy to catch up and come up with countermeasures. All we can do is defend the fortress—— At the very least the country will be safe as long as the 「Huaca Tunnel」 is in our control, but if it were to fall into enemy hands, they'll be able to spread out and take over the world. We once considered negotiating with the enemy, but we encountered a big problem—— ——We don't even know the name of the enemy country or who its leader is. All we know for sure is that there is a 「mastermind」 behind the Honkai beasts. We've also sent 「exploration teams」 composed of 「Star Whisperers」. However, even when they stepped a thousand leagues into enemy territory they couldn't find anyone to talk to. The Honkai beast that attack our fortress come out from beyond the walls so we suspect the enemy's headquarters must certainly lie beyond the energy walls. I can't believe it... ...If 「Napoleon」 has become a monster as well then anything can happen. There's a very high chance he's gone mad. ..... May I ask you something, Rowland-san? Huh? You don't need to be so formal... what did you want to ask? Don't mind that, she's like that with everyone. It might seem a little creepy at first but she doesn't mean anything bad by it. What were you going to ask, Rita? Regarding a certain term you used. Rowland-san, what is a 「Star Whisperer」? ...Hm? You don't know? Let's see... in simpler terms, it's someone like you and me who came from another world, and have innate resistance to Honkai energy. Then how come Dudu knows you who are but you don't recognize it? Isn't that weird? ...It's probably because I have no memories of my life before I came to this world. I think whatever experiences I had in another world have nothing to do with my current self. People can't change the past nor experience the future—— Because we're all living in the 「present」. Ah... was I too serious? Well, once everything is over I might try to find out what that 「Rowland Furioso」 was like. But right now, as a soldier of the Republic, I think it's better if I 「don't know」. Sorry, I'm not good at this 『Clockwork Orange』-like talk. Amid the awkward mood, noise began to be heard during their communication. That noise gradually increased until the video call was cut off. That event serves as proof of the 「Caledonia」 deep diving to a place where radio signals can't reach it anymore. Rowland inspected the submarine's equipment with great interest, and enjoyed Rita's cooking. Then, perhaps out of concern for Dudu, began to share funny jokes from the Republic. She didn't seem to mind her memory loss and embraced her new life in this world. ...When she thought about that, Bianka felt slightly envious of her. The next day—— Wow! So this is South America? It reminds me of the Alps! Not surprising, we're 47 degrees South, almost the same latitude as Zürich. Achoo! ...So cold. I should have brought a jacket. Geez... would it kill you to be more sentimental? The entrance to the 「Huaca Tunnel」 is on the valley past the canyon, but... Before we go, do you mind if we make a quick stop here? ...? The soldier took off her armor in front of the stone monument. The wildflowers of early Autumn gradually took the form of a wreath in her hands. 「We wanderers, ever seeking the lonelier way, begin no day where we have ended another day; and no sunrise finds us where sunset left us.」 「Even while the earth sleeps we travel.」 「We are the seeds of the tenacious plant, and it is in our ripeness and our fullness of heart that we are given to the wind and are scattered.」

注：

这段文字引自黎巴嫩文豪纪伯伦（Gibran Kahlil Gibran）的《先知》（The Prophet）。