Though he was aware of the decision made by the Empire, Vahn was a little surprised by the fact they didn't even try to send anyone to reclaim the Hell Express. They had concluded that it would be a lot safer to send their people in during the six month period where the train docked at the Last Station. This, combined with the fact they had 79 of the 100 total Express Tickets allowed Vahn and his growing retinue of Regulars to freely explore, collect treasures, and train.
With the addition of Elaine and Alphine, there were now ten inordinately powerful Regulars in Vahn's charge. This included Yura, David, Anna, Vicente, Daniel, and, to a lesser extent, Weiss, Arryn, and Arusha. As for Angel, she had already found someone to settle down with among the residents of the Second Layer, and, though she was still determined to obtain her revenge, it was far from her primary focus.
Since even the weaker members of the group were capable of clearing the challenges of the Hell Express, Vahn had given everyone permission to wander about individually but encouraged them to travel in small groups. Instead, everyone decided to travel in one large group. More specifically, they wanted to follow along with him, as, compared to traveling alone, it was always better to be close to the person with a portable 'resort' and a seemingly endless supply of delicious food.
Though he would rather they become independent, much like Team Wolf Pack, Vahn knew the situation of people like Weiss, Elaine, Alphine, Arryn, and Arusha didn't exactly allow it. The same could also be said for the Arie siblings, so, while it was a little inconvenient, he decided to watch over them until he could find a place to safely deposit them. Given the circumstances, this would most likely result in them becoming members of Wolhaiksong. The organization was well known for taking in exiled members of the Ten Great Families, so, with few other options available, Vahn was willing to indebt himself to Ureko if it meant he could ensure their safety while subsequently removing them from his responsibility...
With the door to the Hidden Floor firmly sealed until the Hell Express had cleared the 43rd Floor, Vahn decided to focus on the promise he had made with Daniel, Po, and everyone else related to Roen. Unfortunately, this had become considerably more difficult due to the fact that much of her Ego had been absorbed and subsequently destroyed following her self-sacrifice to seal Hoaqin.
Simply put, it was possible to revive Roen, but, due to her Ego having become a part of the billions of fragments that comprised Weiss, she would effectively be a different person. She would have no memories of her previous existence, and, depending on the circumstances, even her Innates would have changed drastically.
Fortunately, while it was impossible to openly discuss, there was still hope. Roen had completed the Hell Express numerous times in the past, so, while it wouldn't truly restore her original self, it was possible to acquire the 'data' of Roen from the Hidden Floor. Said data could then be infused into the resurrected Roen, and, though she would technically be a different person, her soul and memories would be the same as the original.
Since it would require Roen entering the Hidden Floor for the procedure to be conducted, Vahn spent the three-month period between the 40th and 43rd Floors searching for the Hell Express' core and recovering her spirit. The hardest part of this process was purifying the negative energy and filtering through the countless spirits that had died onboard the Hell Express. He also needed to come up with an alternative power source, as, without the negative energy generated by the spirits, the hellish locomotive would be stranded within the 'Dimensional Gap' separating Floors.
In the end, the vast majority of Vahn's time was spent creating a modified 'Spirit Gathering Array' alongside Eva. Despite its name, this particular formation had nothing to do with gathering spirits. Instead, it drew power from the functionally infinite Shinsu provided by the Elemental Pylons used to draw inert energy from the void and convert it into the standard form of energy existing within the Records. This was actually one of the first formations Vahn had ever mastered, but, compared to the version he had installed to power various barriers and wards back in Danmachi, the current iteration made his past attempts seem rudimentary in comparison.
With the Hell Express no longer relying on the negative energy generated by the deceased, Vahn performed a Grand Purification Ritual, penultimately exorcising all the spirits gathered within the Core. Part of him had been tempted to return them to life, but, unlike Roen, he had no particular reason to do so. In fact, were it not for the promise he had made with Aka, Sachi, Boro, Daniel, and Po, Vahn would have simply allowed Roen's soul to move on to the next life.
Fortunately for the bereaved quintet, Vahn was a man of principle who firmly believed in the value and importance of keeping his promises. Thus, while it might have been better to just let her soul move on to its next incarnation, Vahn's final act prior to disembarking on the Floor of Death was to create a Soul Binding Formation to resurrect Roen's spirit into a body functionally identical to her original. This time, however, the body was provided courtesy of Urahara and the Research Division rather than produced from his own flesh and blood...
Using his ability to view and know everything occurring within the Little Garden, Vahn watched with a thoughtful smile on his face as Daniel tended to the largely unresponsive Roen. She was basically an infantile amnesiac at this point, but, much to his surprise, she had actually reacted positively to Daniel's presence following her revival. This was a positive sign as it demonstrated that, while her Ego was almost wholly erased, a few of the most intrinsic parts of her character had been preserved.
Though it was a little awkward entrusting a 700+-year-old man to take care of an infantile woman, feeding, cleaning up after, and even bathing her, Vahn knew that Daniel's affection towards Roen was sincere. The man had been willing to give up everything just for a chance at restoring her to life, so, while these moments were bound to become awkward memories, he allowed the former FUG member to look after the surprisingly Nami-esque woman in the hopes that it would help to stabilize her Ego in preparation for the transplantation of her Data's memories.
Seeing Daniel patiently feeding the perpetually smiling Roen with a plastic spoon, Vahn couldn't help nodding his head in approval before promptly departing the Little Garden. There, he found Fenrir and Ryun waiting for him, both standing near the open exit of the Hell Express.
Walking over to join the duo, Vahn habitually stroked their heads as he gazed down at the vast sea of blood below. He found it strangely discomforting to consider that several thousand kilometers of the 43rd Floor were dominated by the corpse of a single monstrous entity, the Floor Guardian killed by Enryu nearly ten-thousand-years ago. Despite this inordinately long period of time, there was still a veritable ocean of blood covering much of the Floor, and, according to Ryun, there was an entire civilization living 'within' the Guardian's corpse...
Seemingly sensing his thoughts, Ryun joined him in looking down at the sea of blood, saying, "We will need to jump from here. Though the Guardian has been dead for millennia, its cardiovascular system and several of its organs are still functional to this day. The only way to reach the true Floor of Death is by riding the currents contained within the Sea of Blood. Don't worry. Despite its name, the Sea of Blood is actually comprised entirely of Shinsu. Even if we get stuck in current for several hours, we won't have to worry about suffocating or anything like that..."
Though the idea of breathing in the Guardian's 'blood' was a little disconcerting, Vahn just nodded his head in response to Ryun's words before stepping out of the Hell Express and diving head-first towards the vast sea of energy below. Fenrir and Ryun immediately followed suit, bodies shrouded in vibrant blue and scarlet auras that allowed them to descend into the blood-colored sea without producing a splash.
As Ryun had stated, the interior of the Sea of Blood wasn't simply breathable, it was almost like an oxygen-rich environment. Those entering within would feel extremely invigorated, and, so long as they could resist the powerful current and ever-increasing pressure, it was possible to strengthen both your body and reserves simply by staying immersed.
Unfortunately, unless they were an Irregular or possessed a special ignition weapon, specifically the Thorn, even the most powerful High Rankers wouldn't be able to stay within the Sea of Blood for long. The peculiar red Shinsu was actually the internal reserves of the Guardian, so, unless they had the ability to manipulate the internal energy of a continental sized creature, using any Shinsu-related abilities within the Sea of Blood was simply impossible. Even Vahn was no exception to this, but, unlike the vast majority of people, he had a functionally unlimited amount of energy to make use of within his body.
Thanks to their internal reserves, Vahn, Fenrir, and even Ryun could move about freely within the Sea of Blood. They were not wholly dependent on the Shinsu within the Tower, and, had she been present, even Yuri would have been able to fly around thanks to her elementary mastery of Ki. This was the true benefit of being an Irregular, as, unlike the residents of the Tower, those born outside were aware of the existence of various other forms of energy. Thus, even without Shinsu, they were able to continue fighting, and, in some situations, there were some who became far more powerful in its absence...
With Ryun guiding the way, Vahn and Co were able to avoid most of the hazards that generally prevented outsiders from entering the Floor of Death. This included many parasitic organisms, Gatekeepers, and a number of other strange, often immortal, creatures that called the Guardian's corpse their home.
Though it wasn't particularly well-known, largely due to the fact that even those aware of the truth were unable to disclose it, the Elder of the Red Witches had contracted with Enryu to ensure that the prophecy regarding Jahad's death was brought to fruition. Because of this, the 43rd Floor had become an important pilgrimage site for the Red Witches, and, thanks to Enryu's influence, it was one of the few places in the Tower where even Jahad dared not venture. After all, the contract that guaranteed the immortality of Jahad and the Ten Great Warriors was just that, a contract. With the death of the Floor Guardian, the 43rd Floor was one of the few regions in the Tower where Jahad's Immortality simply didn't function.
As one of the daughters of the Red Witch Elder, effectively making her a Princess of the Red Witch Tribe, Ryun was one of the few people that knew about the contract with Enryu. He had promised to free them from the Tower and create an endless number of new and interesting paths for them to view. Thus, for the last several millennia, the Red Witches had worked closely with FUG and it's constituents, patiently awaiting the day when the 'way forward' would be opened.
Were it not for Vahn's unexpected arrival, Ryun would have given up everything, including her own life, in order to allow Baam to kill Jahad. Fortunately, this was no longer necessary, as, even without defeating Jahad, the way forward would be open. It was for this reason that she worshiped Vahn to such extremes, as, rather than devoting herself a prophecy that required countless sacrifices, it was a lot more assuring to follow a God that took matters into his own, inordinately pleasant, hands...
(A/N: Alternate Titles: 'Vahn be like, "Stay with Aunty Ureko. I'm gonna go out for a smoke..."','The Guardians are some big bois...','Ah, yes, the most pleasant of hands (O w O)...')
https://bit.ly/2XBzAYu <-(p.atreon link)
Discord Invite: https://discord.gg/Jwa8PKh