Japan, 1615.

The Summer Siege of Ōsaka had been brought to an end. The Toyotomi Clan had finally been suppressed with the death of Toyotomi Hideyori and his mother, Yodogimi, along with their most valued supporter, Sanada Yukimura. As far as the world was concerned, Sanada had made one final charge toward the Tokugawa camp, only to be gunned down by the enemy riflemen as he duelled Hattori Hanzō.

In truth, it was his trusted retainer, Sarutobi Sasuke, that had died in his place. The real Sanada had come to realise that his lady was not herself, and had joined forces with the so-called 'Golden Samurai', William, to put a stop to her destructive ambition. After exorcising Yodogimi of the kyūbi controlling her, Sanada had stayed with her inside the keep of the burning castle, while William made his escape. William and Hanzō were the only two alive that knew the truth of Sanada's fate.

Two months had passed since then.

William was in his home, awaiting the return of his wife and son from visiting the boy's grandfather. William had been officially gifted the rank of samurai and given a home after marrying Okatsu, daughter of Shogun Tokugawa Ieyasu. The union between the Shogun's daughter and the Irish-born Englishman had proven quite controversial among Ieyasu's advisors.

However, Ieyasu would not be swayed into disallowing it, seeing how William had proven integral to the defeats of Ishida Mitsunari, the foreign necromancer Kelley, and the Toyotomi; even if only the most trusted of Ieyasu's advisors were above the Shogun's official records that heavily downplayed the presence of the foreigners on both sides. Plus, Okatsu had been rebellious towards her father since the death of her brother, so swaying her would be nigh impossible anyway. And William and Hanzō both suspected that the seventy-two-year-old's days were numbered, and that he was hoping to make peace with his daughter before the end.

William was currently relaxing in the sheltered natural hotspring at the back of the house he shared with his new family. He heard a very light tapping on the roof above him, which he recognised immediately.

"You're on the roof, Hanzō!" he called out.

Sure enough, an older man clad in traditional ninja garb slowly and quietly dropped down from above William. This was a common way for the master ninja to make his entrance into William's house - to test both the home's defences for weak spots, and the owner's perceptiveness to ensure he wasn't getting rusty now that the war was over. Of course, in the event of urgent matters, he would simply use the door.

"You are as perceptive as ever," the ninja said, in English, with a smile. "Good."

Rising from the water and wrapping a towel around his waist, William asked what his old friend's business with him was today.

"You have received a message," Hanzō explained, removing a small letter from his breast pocket.

William took the letter from the ninja, opening it to find that it was written in Japanese. Thanks to Nekomata, William had been able to speak with the denizens of Japan, even without having to learn their language. He had begun to properly learn it since returning from dealing with Kelley's master, John Dee, in England, but even he had to admit his grasp on the language's numerous written forms was poor. Fortunately, he could always rely on Hanzō, Okatsu or Nekomata to read it for him.

"The sender is unknown," Hanzō explained, "but it says, 'The Hayabusa Clan wishes to face the Golden Samurai in combat'. The note was slipped into my breast pocket; when, I do not know."

"Sounds like you're getting careless in your old age, Hanzō," William said playfully. The Japanese were a strictly formal bunch. The only two among them he felt comfortable speaking so informally with were his wife and Hanzō. Their ability to speak English better than he could Japanese likely played a part in that.

Hanzō chuckled. "Perhaps it is time to choose the next Hanzō."

"I hope Joseph has an easier time dealing with you than I did with your father," William said, recalling his clash with the previous Hanzō's toad-like yōkai form.

Hanzō chuckled. "I have no intention of becoming a yōkai. Besides, I have seen the boy's tenacity. At my age, I would not stand a chance."

William smiled while looking over the letter. Even without being able to properly read it, he found that he could instinctively identify 'ハヤブサ' as 'Hayabusa'. "Hayabusa," he uttered thoughtfully.

"You are familiar with the name?" Hanzō asked from his side.

"Oh, no. I might have heard mention of it in my travels though."

This was a lie, of course. Fortunately for William, as Ieyasu had observed, Hanzō was not a very good liar, and that made it difficult for him to spot lies in others. In truth, William had heard of the enigmatic Hayabusa Clan; just not in this world.

It had been while storming Ōsaka Castle alongside Sanada Yukimura that a sense of familiarity had begun to wash over William. Although curious, he had pushed the sensation to the back of his mind to focus on stopping Yodogimi. He had had some time to think on it later, after Sanada had died, when another familiar feeling found him. This was the one that had gripped his heart upon meeting with Tachibana Muneshige for the first time since his return to Japan, and learned that Muneshige's wife, Lady Ginchiyo. had passed a mere two years after Sekigahara. It was the feeling of having lost a valued friend.

Of course, while the two had set aside their differences to stop Yodogimi, William would hardly consider Sanada a friend. As he ruminated on these odd feelings, a hazy memory emerged, like a long-forgotten dream briefly recalled in a moment of déjà vu. And now, the name 'Hayabusa' served as a key to unlock to the door to this mysterious memory.

It was as William was preparing to depart for England to deal with John Dee over fifteen years ago. As he was moving some supplies onto his ship, he was suddenly engulfed in an otherworldly light, which eventually subsided to reveal a strange harbour town with buildings that looked to be a mix of Japanese and European design.

There, he was attacked by an army of yōkai types both familiar and unknown. He met up with a pair of ninja named Ryu Hayabusa and Ayane, who reminded him a lot of Hanzō and Okatsu, serving as the first bit of comfort he found in that strange world. The three were recruited into a war by a human-dog hybrid named Shiki, and helped to save that world, alongside two dozen other summoned warriors. Their memories of the conflict had been sealed as they returned home, but not so heavily as to be unrecoverable.

He wondered if, perhaps, Hayabusa and Ayane might actually be from the same world as himself, but from another time. Hayabusa had claimed to be from the far-off year 2018. If that lined up with William's world, Hayabusa and Ayane were from four hundred years into the future. If that was the case, then Japan's yōkai problem would one day go away, only to give way to creatures known as fiends.

William now understood the strange feelings he had towards Sanada Yukimura. Among his allies were the Yukimura and Ishida Mitsunari of another world. William fought most of his battles alongside Hayabusa and Yukimura and the three became good friends over the course of their service. He had enjoyed learning about the counterparts of those he had fought alongside and against from Yukimura, and vice-versa. He had also learned a few ninja techniques from Hayabusa, which he had subsequently forgotten upon his return home, but he now felt like he could perform them flawlessly.

Meanwhile, fighting alongside the other Mitsunari had been a strange experience, in light of William's clash with his world's Ishida at Mount Ibuki. He and Yukimura had been joined by their world's Ii Naotora, supposedly the adoptive mother of Ii Naomasa, whom William had assisted shortly after Sekigahara. But, of course, nothing quite compared to the strangeness of the human-ish feline warlord, Oda Nobunyaga.

"What do you know about this Hayabusa Clan?" William asked suddenly.

"Unfortunately, nothing," was Hanzō's response, which surprised William. Hanzō was Ieyasu's primary spy and the head of the nation's most famous ninja sect. That even he didn't know anything about this other clan meant his challenger was truly the most enigmatic foe he had yet faced. Fortunately, having sparred with a man he supposed with his challenger's descendant or successor, William had something of an advantage here.

William stepped back inside and began making preparations. He was overcome with a strange, almost nostalgic excitement. Even if it wasn't Ryu himself (though from the excited string of theorisation Honoka had unleashed, it very well could be), the opportunity to fight someone with that style again was enticing. His fights with Yukimura must have awoken something within him.

"But I do know," Hanzō continued as he followed William inside, "that it would take an incredible amount of skill for them to slip the challenge into my pocket without being detected. If it was the individual who intends to duel you, they must be a ninja of the highest ability. If you decide to accept their challenge, I recommend you do so with great caution."

William took the new katana he had received from Ieyasu as a wedding gift from its place on the sword rack and checked for dulling. "If he's as stealthy as you say, he could easily have snuck in here in the night if he'd wanted me dead. It's not like anyone would know to accuse this enigmatic Hayabusa Clan of committing the deed. He likely just wants to test himself against the skilled foreigner he's been hearing so much about."

"I hope so," Hanzō sighed. "Still, I would rather not take that chance. I will shadow you and help you escape in the event of foul play."

"I won't say no to the help, but I want you to be careful as well. If they could sneak a message into your pocket, they can probably spot you without much trouble."

"True enough. I will be mindful of their skills in my reconnaissance."

And with that, William donned his armour and gathered his weapon, before departing for the designated location alongside Hanzō.

The location was some ways east of the remains of Ōsaka Castle. The directions pointed towards a small cliff edge, covered in tall grass, from which the moon could be seen shining brightly in the sky. William had fought duels in locations similar to this all across the nation, as numerous famous samurai had sought to test themselves against him. The area appeared devoid of any human or yōkai life. Despite that fact, there was an ominous air around the clearing. Knowing he was safe in Hanzō's hands, William proceeded forward.

As he approached the centre of the clearing, the Hayabusa ninja made his presence known. He suddenly leapt from a nearby tree and landed as gracefully as his descendant would by the edge of the cliff. He rose to his feet, silhouetted against the moon, and crossed his arms in that all-too-familiar manner.

His attire was a sleeveless take on traditional ninja garb in a medium blue, with red bands covering his forearms. While the attire was considerably looser than Ryu's sleek black attire, William could definitely see how this style of dress could one day evolve into Ryu's. Especially as his stood with his arms folded and his scarf billowing in the wind. Like ancestor, like descendant, William supposed.

"You must be Jin Hayabusa," William said, having absolutely zero doubt that he was correct.

"And you are William, the Golden Samurai," the man replied in English, surprising William. In all the years he had spent in Japan, the only Japanese he had had anything close to a conversation in English with were Hanzō, Okatsu and Date Masamune.

"I'm curious, Hayabusa: why do you want to duel me?"

"Best me and you will have your answers."

With that, the ninja drew the sword from his back and took his stance. The weapon and stance were unmistakeably the Dragon Sword and the Hayabusa Style. William had only a moment to take note of this before his opponent was rushing towards him. He just managed to get his own sword half-drawn to block the incoming strike. He kicked at the ninja, who dodged back, buying William time to draw his sword fully.

William had sparred with Ryu a number of times and had a good idea how the ninja's sword style worked. But, there were two issues with that here. First was that, assuming William was correct and Ryu was from the future of this world, his version of the style was much more refined after four centuries, which made Jin's movements less predictable. The other was that Ryu had fought exclusively with his Dragon Sword. Jin, however, was also packing a kusari-gama and swinging it in a manner William had yet to encounter in either world. His ability to quickly switch between weapons was a skill few of William's opponent had mastered, and it was impressive.

The battle was a short one, but it was still one of the most intense William had yet fought. True to his name, this Hayabusa was swift as a falcon, and would surely have been as deadly, were he not facing a warrior of William's calibre.

It was when Jin began utilising ninja magic William had seen neither Ryu nor other ninja utilise that William called on Saoirse to empower his weapon. With her acting as his Living Weapon, William was able to clash against the Hayabusas' legendary heirloom and push Jin back. William's blade pushed through and managed to leave a cut down Jin's chest. The blow was a shallow one, but Saoirse's power made it more damaging without being life-threatening.

"Your skills are impressive," the ninja panted, holding out a hand in defeat. "One would almost think you had faced the Hayabusa style before."

William chuckled nervously, deciding it best not to discuss his glimpse into the Hayabusa Clan's future. Instead, he withdrew some medical supplies from a pouch on his belt and offered them to his opponent. Jin gratefully took them and began tending to his wound while William sat on a nearby rock.

"I'd consider you bested now," he said with a grin. "So, about my answers."

The ninja chuckled at the nerve of the foreigner. "You asked why I wanted to duel you. I think you have earned the answer, yes. The Hayabusa Clan protects Japan from the threat of yōkai and other evils from the shadows. But the resurgence of spirit stones in recent years has worn us thin and claimed the lives of many of our best. Then, word reached us of a mysterious foreigner taking part in numerous battles and slaying some of the most powerful yōkai in the country. And more, that the Shogun was attempting to cover up his role in official records. There were even rumours that you fought Oda Nobunaga himself when the necromancer tried to use him as a tool in his wicked schemes. We knew, eventually, our best would need to test his skills against you."

"To make sure your metaphorical blade has not dulled in your clan's absence."

"Precisely. Alas, it seems we are falling behind."

"For what it's worth, you put up a hell of a fight. I've not had a fight like that in quite a while."

"You flatter me, Sir Anjin. But I have disgraced the Hayabusa name this day."

"As long as you're tough enough to protect your people from yōkai, you shouldn't consider yourself a disgrace. Besides, officially, I'm just a sailor here arranging trade with England. I'm fairly certain that makes you the toughest in Japan."

Jin laughed out loud in spite of himself. "Your tongue is as sharp as your blade, Sir Anjin. I see why the Shogun turned around on you after your return."

"I'll gladly accept a rematch when you've improved and want to test your skills again." William held out a hand, which the ninja took gladly.

"I will hold you to that, Golden Samurai."

Once he was healed up, Jin departed, leaving William alone in the clearing. At least, until Hanzō appeared.

"I was beginning to worry his boys had gotten to you," William joked.

"There were none," Hanzō reported. "He really did come alone. Whether that speaks to his honourable intent or his confidence in his ability to neutralise any support, I cannot say."

"After fighting him and talking with him, I think it was both."

"Still, offering a rematch is not something I would expect from you."

"What can I say? I'm curious to see where the Hayabusa style can go from here."

Two years after his duel with Jin, William was once more summoned to the world of Shiki, Setsuna and Tamaki to fight against another evil entity. Once more, he was joined by Ryu, Ayane, Yukimura and many more.

As before, William and Ryu were among the first to meet up and arrive at the Sacred Spring. They spent some time catching up on what they had each been up to since their last summoning. William explained his return to England; his encounter with Date Masamune; the birth of his son, Joseph; his participation in the two Sieges of Ōsaka; and his alliance with the shiftling, Hide, which finally brought an end to the machinations of that Spanish ninja.

Not nearly as much time had passed for the Hayabusa ninja, but he observed that Ayane's relationship with his sister, Kasumi, had improved some since last time. William had always compared Ayane's guarded, often standoffish demeanour to Okatsu. He couldn't help but chuckle at the though that, much like his wife, the purple-haired kunoichi was also starting to open up more.

As they sat at a table in the tavern by the Sacred Spring, they were joined by Yukimura and Oda Nobunyaga. Oda observed that the other three were the most personable of those summoned from their respective worlds. Naotora was a shy, easily flustered mess, while Ayane didn't much care for socialising.

"They do make for an odd pair," William noted, recalling the strange bond the two had formed last time. "But then, so do my wife and me, so who am I to judge?"

"I don't recall you saying you were married last time," Ryu observed.

"That's because I wasn't. After I returned to my world and my business in England concluded, Okatsu came to see me up in Tōhoku and... well, one thing led to another."

"Congratulations, Lord William," Yukimura said earnestly.

"Thank you. Are you married, Yukimura?"

"I am not," the red-clad samurai responded, seemingly a little embarrassed by this fact.

"Ah, dedicated to your training, are you?" Nobunyaga said with a nod, though whether he believed this or was simply trying to alleviate Yukimura's uneasiness with an easy way out, none of the humans were quite sure.

"Something like that."

"The Sanada in my world was married," said William. "He inherited his father-in-law's guardian spirit after he died. He was one of the few people I've ever known to be able to wield two spirits at a time. I hear Nobunaga could too, of course," he added, receiving a satisfied nod from the warlord's feline counterpart.

"And you said you fought my counterpart?" Yukimura asked. "What was he like?"

"He was honourable to a fault. He refused to use amrita, despite the advantage it would have provided, though he wasn't opposed to using a pistol when the need arose. And he chose to stay with his mistress as the castle burned around them. His fighting style was similar to yours, but certainly more aggressive. You and he are very similar, which I suppose is to be expected. I just hope your fate is a brighter one than his."

Yukimura nodded silently as he took in William's words. It was Nobunyaga that broke the silence at their table.

"You have told us much about my and Yukimura's meownterparts. But, what of Hayabusa? Does he exist in your world as well?"

"I am from a time long after the Warring States," Ryu interjected. "Although possible, it's doubtful I have a counterpart there."

"Ryu doesn't exist there, as far as I know. But I did meet one of the Hayabusa. Said his name was Jin."

Ryu choked out a sound of exclamation. "Hayabusa... Jin," he muttered.

"I take it you've heard of him."

"Yes. Jin was one of my ancestors from the Sengoku period. He is considered one of the greatest of out lineage."

"I can believe it. He put up one hell of a fight."

"You... fought him?" It was rare for Ryu's cool demeanour to break, so seeing him flounder at William's revelations was amusing to the Englishman.

"He challenged me to a duel not long after the battle in Ōsaka. It was short, but fierce. If not for Saoirse, I doubt I would have won."

"I do remember hearing that Jin lost only one duel after becoming the head of the clan. And it was shortly after the Summer Siege of Ōsaka."

"Then..." Yukimura interjected, putting the pieces together. "You two are..."

"From the same world?" Nobunyaga finished for him, eyebrow raised in intrigue.

"It is possible," Ryu said thoughtfully. "The forms this world takes from each of our worlds doesn't always reflect the times we are brought from, so there's no reason to assume the Heroes were all summoned from the same point in time."

"I've thought as much since I received the letter of challenge. Hearing the name 'Hayabusa' brought back my memories of fighting in this world with the rest of you."

"I had the occasional bout of déjà vu after returning home as well. But I must ask, what was Jin like?"

"A lot like you, honestly. He was a highly skilled warrior with a good head on his shoulders; adept with the sword, the kusari-gama and the ninja arts. That Izuna Drop is hell on the neck."

Ryu smiled at that.

"But his primary concern was ensuring that the Hayabusa were strong enough to protect the world from yōkai. They were in a bad way at the time, and he wanted to test himself against the man he'd heard so many rumours about. He even mentioned my fight with Nobunaga. At the time, it seemed like just an acknowledgement of my history. But, if he knew about that fight, he must have known I didn't win it. Nobunaga beat me and then chose to go back to the afterlife."

"It is good to know my moewnterpart is living up to our reputation," said the feline Demon King.

"The Nobunaga of my world was a force to be reckoned with as well," chimed in Yukimura, prompting another nod of satisfaction from the samurai cat.

"You felt there was something more to his comments?" Ryu questioned.

"I do. I asked Hide about it, but... well, Hide isn't really the talkative type."

"I might be able to shed some light on this then, assuming our worlds are, indeed, one and the same. In our history, Oda Nobunaga was aware of the Hayabusa Clan's existence and invested heavily into the development of our village. He even commissioned the Hayabusa Castle which, despite three separate attacks in recent years, still remains standing."

Hayabusa was a stoic and measured man. He was friendly enough and easy to get along with, but he wasn't usually open about his clan (for obvious reasons) and his displays of emotion always seemed calculated, as if only exposing as much as he was willing to. As such, hearing the clear pride in his voice as he spoke of his clan's resilience was both unusual and endearing.

"What is the matter, Lord Nobunyaga?" Yukimura asked suddenly.

The warlord appeared contemplative. "This talk of a Hayabusa Clan brings to mind a ninja clan in my own words that I have had dealings with in the past. The Hanyabusa Clan."

Immediately, the three humans burst out laughing, though Ryu's was more reserved than the other two's.

"I suppose it makes sense that, if Oda Nobunaga or Sanada Yukimura could exist in multiple worlds, then so could we," Ryu noted. "Our history stretches back as far as the Heian period - eight hundred years ago for you," he explained, adding in the extra note for the foreigner's benefit. "And for all that time, we have fought to protect the world from yōkai and other dark creatures. And we will continue to do so long into your future."

"That's good to hear. Between you and him, I can tell you're a powerful bunch. I suppose I can rest easy, leaving the slaying of yōkai in your hands in the future."

"I... am strangely humbled by your words, William. Or rather, Sir Anjin."

"Please, don't start with that..."

This time, all four of them laughed. At the same time, William wondered how well Hide would fare against one of the Hayabusa Clan, seeing how William and Hide had seemed evenly matched in their own clash.

Meanwhile... or technically, 641 years prior, the timetravelling Hide was summoned to an underground cave by a message left with Nekomata.

"Are you friend or foe?" asked the voice of the summoner. "Let me put you to the test!" Seconds later, Hide was confronted by the brutal skill of the Heian period's Hayabusa Ren.

Nioh 2's second DLC dropped today and it's fucking sick. Go play it.