It was currently late at night, Chrom was currently in the courtyard of Ylisse's palace. Footsteps could be heard as he turned around, seeing his white-haired friend, along with the Hylian swordsman. He then sighed.

Robin: Chrom? What are you doing out so late?

Y/N: Do you feel ill?

Chrom: Hi, guys. Just...dueling with some unpleasant thoughts... Tomorrow, we march to Regna Ferox to request additional soldiers. But there's something you two need to know first. ...Not everything Gangrel said was a lie. The last exalt, my father, waged war on Plegia for many years. The violence... It was a brutal campaign, ending only with his death 15 years ago. Plegia rightfully remembers their suffering, but his war was no kinder to his own people. As the fighting dragged on, our army became more and more diminished. Farmers who could barely wield a pitchfork were conscripted and sent to their deaths. Soon there was no food at all, and the kingdom began to collapse. I was young, but I remember those dark times. ...I know how they affected Emmeryn. 

Y/N looked away, remembering the times of Hyrule. From his time there, they were at war with Ganon's creatures. Moblins and Bokoblins would raid any nearby villages on the outskirt of the villages, some being taken and rundown as Hyrule's soldiers couldn't get to them in time. 

Not only that, Hyrule had a plethora of history about Ganon taking over the kingdom, people living in a time of despair. And time and time again, a hero of the era would rise up to save it with a princess with a sacred power to seal away the darkness. And yet, in the era he lived in, he failed to do so.

Robin: Such an experience would change anyone.

Y/N: And I doubt the old scars left by it haven't healed yet.

Chrom: (sigh) Indeed. When our father died before her 10th year, he left her quite the legacy... Plegia's desire for vengeance... Our own people's unbridled rage... My sister became a target for blame from all sides. Her own subjects began to hurl insults--and stones. She still bears the scar from one. But she never let them see her pain. Only Lissa and I understood. 

Robin: It must have been so hard...

Y/N: The amount of willpower for her to safeguard such emotions within her... To keep going strong for the sake of her people...

Chrom: I cannot claim to know how she does it, Robin, Y/N. I could never greet such hostility with warmth and patience. While our people mocked her and vilified her, she reached out and healed them. She brought soldiers home to their families. She ended the war. And when Ylisse's spirit was mended the people "forgave" her? ...She never resented them for it. She represents the best of the halidom--the part most worth protecting. She IS peace. But some men would take advantage of that. Men like King Gangrel. The day he understands peace will be the day death gives it to him. ...So perhaps I must be death's agent. Emmeryn would never order him killed, nor would I wish her to.

???: Well spoken, sir.

Upon hearing the two voices, Y/N immediately stood in front of Robin and Chrom, a hand on his sword. Chrom did the same as well, seeing two figures walking up to them, Marth and Link.

Chrom: Marth...

Marth: Good evening to you.

Chrom: How did you two get in here?

Link: We have our ways. But if you must ask, it's the cleft in the castle wall, behind the maple grove.

Y/N: (thoughts) A break in the castle's defense?

Chrom: There? But how would you...? Ugh.

Robin: You know the place, Chrom?

Chrom: Yes. I bashed in part of that wall while training the Shepherds. It's only a small hole, and I'd thought it well concealed, but...

Marth: Your secret is safe with us. We came here to only warn you.

Chrom: Warn us?

Marth: The exalt's life is in danger. 

Chrom: What, Emmeryn? That's absurd. She's guarded at all hours. 

Link: What if we were to tell you that we've seen the future. Would you then believe us?

Marth: A future where Emmeryn is killed. Here. Tonight. 

Y/N: ...And why should we believe you?

Chrom: And seen the future? Have you two lost your wits?

Link: Heh. We thought you'd say that. So allow us to prove it.

The masked swordsman drew his sword from his sheathe, causing Y/N and Chrom to keep their hands on their own swords, tightening their grip on the handles. But Link simply brought his hand up, his face still being covered by the shadow being cast from his hood.

Link: Calm down. He's about to save your life. From the one hiding in that bush over there.

And just on cue, a hooded assassin with an iron sword came running out. Marth threw his Parallel Falchion into the air, leaping up and grabbing it before coming back down and slashing the back of the assassin, now dropping dead. Marth then flicks the blood off the blade, his gaze now set onto the three in front of him.

Marth: I trust this proof will suffice?

Chrom: (nods slightly) ...Yeah.

However, another assassin leaped from the trees, catching Marth and Link off guard. Marth tries to back up, attempting to dodge the assailant, but he steps on the sword of the previous dead assassin, slipping and falling backwards. The hooded swordsman reached outwards, calling for his name. 

The other assassin's sword lunges downward, cutting Marth's mask off, revealing the man to actually be a woman, the girl's long hair now being untied as it was being held up by the mask. Y/N could see a hint of fear in the girl's eye. Not just in fear for her life, but also in fear for something else. Before Marth's life could be taken, both Chrom and Y/N had rushed forward, their swords drawn and they cut down the assassin, his body dropping to the floor.

Chrom: (surprised gasp) W-Wait, you're a woman?

Marth: And quite the actress, too. Honestly, I'm surprised you didn't figure it out until just now.

A loud boom could be heard coming from within the palace, causing Chrom and Robin to be alerted, as did the rest of them. Just as Robin and Chrom ran inside, Marth about to go join them, Link grabbed her by her wrist, the girl able to see the hooded swordsman's blue eyes, filled with slight worriness.

Link: You okay?

Marth: (smiles) Yes... Thank you, Link.

Y/N could see that the two shared a bond, perhaps an affectionate one. "More than partners?" is what ran through his mind. Link notices Y/N's intense gaze and simply glares at him.

Link: What? Is it so wrong to care for a precious ally?

Y/N says nothing, simply following after Chrom and Robin. Link narrows his eyes at the Hylian swordsman before he felt a comforting hand on his shoulder, turning to see Marth looking at him with concern.

Marth: Do you think he knows?

Link: No, not yet. But it's best if we keep it that way for now. Keep it from all of them.

Marth: Right...of course.

Link: I know how much you wanted to go and say hi the first time we saw them. I, as well. But for now, we have to establish ourselves as people who are simply watching over them. We can't interact with them too much and have our identities known. Our real ones, I mean.

Marth: I know.

Link: Let's go after them, then.

---

Chrom: Emm!

Emmeryn: Chrom! Take Lissa and flee while you still can!

By now, Chrom, Robin, and Y/N had caught up to the rest of the Shepherds, where they were now safeguarding Emmeryn in her room. 

Chrom: No! We're not leaving you! Just stay where it's safe!

Robin: The assassins should scatter if we can defeat their leader. 

Marth and Link were just a few feet behind Y/N and the others when they stopped. Marth took a look down at her waist, causing Link to stop as well and grasp her hands.

Link: What's wrong?

Marth: Falchion is gleaming... 

Link: (whispers) Is that a problem?

Chrom: (turns to look at two) What's wrong?

Marth: (shakes head) It's not your concern.

Chrom: (sighs) Seems like nothing ever is with you two.

Marth: Our apologies. 

Chrom: Just stay by Emmeryn's door. We'll handle the killers.

Emmeryn: Chrom, please! Flee while you still can! Y/N, take them and go! You each have but one life, and I do not wish it weighed against mine!

But Chrom and his Shepherds were defiant, determined to stand guard at Emmeryn's side. As per usual, Chrom and Robin gave Y/N free will as what to do on the battlefield, so he was acting on his own. At the moment, Y/N thought it best to stay in the vicinity of Emmeryn's door so he could safeguard it. 

One of the ruffians had moved up, raising his axe above him as he goes for an attack on the Hylian, thinking he could overtake him. But Y/N raised up his metal shield, the axe bouncing off of it as it struck the shield, Y/N quickly retaliating as he drove his sword through the ruffian's chest. Y/N then kicks him off, quickly flicking the blood off towards the floor and preparing to fight his next opponent, which were two assassins. Though, Y/N himself had experiences with assassins before.

Back in Hyrule, there was a splinter group of the Sheikah that supported Calamity Ganon. They were known as the Yiga clan, and many attempts on his life had been done, but they never seemed to succeed. He knew why he was targeted. After all, according to legend, he was the supposed brave knight that wielded the sword that seals the darkness. 

One of the assassins had jumped into the air, then coming back down, spinning like a buzzsaw. Y/N raises his shield for defense, gritting his teeth as he could feel himself being pushed back, the assassin's attack hitting his shield multiple times. The other sees this as a chance to attack, him rushing in as his ally backs up, now heading for Y/N. However, Y/N was quick to respond, him jumping out of the way as he lands and jumps up before bringing his sword down, plunging it down onto the enemy assassin, killing him. But there was still the other one, the other assassin rushing in with his sword, slashing in with a reverse hand grip.

Raising his shield once more, he blocks the attack, crouching down and sweeping the ground with his own blade. The assassin dodges it by jumping into the air, quickly going into his pouches and throwing knives towards Y/N, the Hylian quickly putting his shield and sword away as he dive rolls to the side. Once recovering from the roll, Y/N draws his bow and takes an arrow from his quiver, drawing his bowstring with the arrow back before letting it go, the arrow flying at quick speeds.

It sped towards the assassin, who had cut it down like it was nothing. The assassin thought he had the upper hand, grinning as he came down to slash Y/N down. But his eyes widened as his mouth was slightly agape as he felt an impact in the side of his head. An arrow had pierced him from the side of his head, killing him. The assassin failed to notice that Y/N had quickly drew another arrow from his quiver and aimed it to the side slightly, it being fired and curving around a stone pillar before it struck him in it's head. With the assassin now dead, it's corpse drops to the floor, Y/N letting out a sigh of relief. 

The blue-eyed warrior then notices a woman appear out of the shadows. Despite coming from a world that had bird men, living rocks, and humanoid fish, he was surprised to see that the woman was bearing rabbit-like features on her head.

???: (sigh) I knew there was wisdom in slipping in with these rogues. Look how these man-spawn claw at each other like savages! I will repay my warren's debt and then wash my hands of their race.

Chrom: (alarmed) Another assassin?

Marth: Hold! Panne is not your enemy.

Chrom: You know her?

Marth: I know...of her. And I knew she would come here tonight.

Y/N: You are quite the prophet, aren't you?

Link: It's as you said. We swear to you, Panne is an ally. 

Chrom: ...Good enough for me. All right, Shepherds! For now, we leave this Panne character be.

Fredrick: Is that wise, Milord? 

Chrom: Marth and Link has earned our trust. They enjoy their secrets, I know. ...Like her gender, for one. But she's also saved our lives. Twice. And that's enough for me. 

Marth: Chrom... Thank you.

Link: Likewise. 

Chrom: Now to the matter at hand: driving these scoundrels from our castle! 

The woman known as Panne then let out a battlecry, running into the swarm of enemies in front of her as she held a stone in her hand. It seemed to glow, Panne then morphing into a giant rabbit, making Y/N surprised. He's seen many strange things in his line of work, but none as strange as a woman able to morph into a giant rabbit.

Y/N then shook his head, returning to the task at hand. He sees Chrom and Robin running to the castle's courtyard, where a man who was different from the rest stood. He wore Plegian clothes, but it were ones of a sorcerer, as the man was accompanied by many tomes on his person. The tactician and prince were rushing in to head towards the man, three Moblins and a few brigands going to meet him. Putting his bow away, Y/N runs over to a nearby pillar and began to climb, him being able to fit his fingers into the crevices and cracks of the pillar as he began to ascend.

(A/N): This kinda makes sense as in BoTW you can climb literally anything. Even if it doesn't even look climbable in real life.

Making it to the top of the castle, he draws his bow once more, taking a few arrows and taking aim. He took a steady breath, emptying his lungs of air as he began to focus. Letting go of the bowstring, his arrows begin to fly through the air as they fly past Chrom and Robin's heads, striking three of the brigands in their chests, right in their heart. The Moblins and the two look to the roof, seeing Y/N jumping off and descending down with his paraglider, now right on top of them. Putting his paraglider away, he swiftly took out his sword and began to dive downwards, his sword pointing down as if he was going to stab it in a sword pedestal. Y/N then lands on top of a Moblin, his sword piercing the Moblin's head.

The Moblin falls to the ground dead, the other two Moblins beginning to surround him as Y/N got up, looking to the prince and tactician. He sent a nod their way, Robin and Chrom nodding to him as well as the two run off to take on the mysterious sorcerer. This left Y/N to deal with Moblins, of which he had no problem with dealing. He took out his shield and did a back flip, dodging a swing from one of the Moblin's club. Once landing, he jumped to the side to dodge the other Moblin's club, it slamming it down. Y/N was quick to counterattack, quickly dropping a cube remote bomb onto the ground, putting his shield away to draw his Sheikah Slate from his belt waist. He clicks the button, the bomb exploding as the two Moblins fly in the air, Y/N drawing his bow after putting his sword away. Quickly aiming at the Moblin towards the left, he draws an arrow and pulls it back, letting it go as the arrow accurately strikes the Moblin in it's head. He then puts his bow away and draws his sword, aiming before he throws his blade, it flying through the air in a circular motion before it impales the Moblin in it's chest.

Y/N then checks on the tactician and the prince, whom have finished their opponent as well. The sorcerer seemed to be angered that their plan having been found out, but he soon grinned as he slowly chuckled and pointed to the sky, his arm soon falling limp.

The three were confused as to why he was pointing upwards, so they looked up. From there, they saw a red blood moon gracing the night sky, the skies soon turning red as well as they felt an ominous feeling. It was then, Y/N could hear that familiar voice again.

...

Y/N... Y/N... Be on your guard. 

A monstrous roar could be heard in the night.

Ganon's power grows...it rises to it's peak under the hour of the blood moon. By it's glow, the aimless spirits of monsters slain in the name of light return to flesh. Y/N...please be careful.

The moon's color then returns to normal, but the princess's warning was proven right. Robin and Chrom were alarmed as the three Moblins Y/N had slain had suddenly come back to life, the monsters getting up as they grabbed their weapons, growling at them. Y/N rolls out of the way as a Moblin came up to him and slammed it's club down, Y/N drawing his sword and slicing upwards, cutting off it's arm. He then climbs on it's back and begins to repeatedly stab it in the neck, the Moblin trying to shake him off before he falls over, dead. 

The other two Moblins were felled by Chrom and Robin, the three looking at each other as they wondered what just happened. Not only did this mysterious blood moon bring the dead monsters slain the name of the light back to life, they heard a monstrous roar, one they haven't heard before.

But Y/N felt like he's heard of it before. The monster that had growled was the one that was waiting for him, so he could defeat him and devour the land.