The data provided by the science department on time manipulation experiments showed slower progress than he had hoped for. They were making progress, but Momonga couldn't be assured that Ker wouldn't make her next strike in the next month or maybe even in the next few days. While he was assured that she would be unable to kill him permanently, Ker could still take away those he cared for, in turn limiting how he could buff up his allies.
Thus, his best bet was to perform experimentation of his own and push Omniscience to its limits in hopes of gaining the much-needed knowledge on how to move between timelines. The challenge was that the world system Veldanava had set in place didn't permit such a thing to occur, Chloe's skill was more of an anomaly and not too useful at that. Sure, Chloe could try to escape into the next timeline should things go terribly south, but that didn't help him in any way and he had blocked her ability to use that skill so she didn't attempt to do so if, for example, Luminous committed suicide and destroyed her soul so she couldn't be revived, knowing the connection between the two.
As his three consorts soundly slept beside one copy of him, grasping various body parts with love, another sat on the Throne of Kings ready to experiment. The Omnipresence had done wonders for his productivity as he could leave a part of himself in the embrace of three women while the rest of him worked elsewhere, merging back together later and fully experiencing all the individuated parts.
First, he suspended the world with Time Stop and inspected the time dimension that affected this world. The first thing he noted was that it was so tightly knit that there wasn't a single loose strand to utilize as an opening, no matter how hard he pushed the skill. There was no perceivable way he could move in any direction and Omniscience working within the confines of the system only enforced the notion of time being unchanging, with only its complete suspension possible. Even then, there was a huge checklist of requirements before even that could be exploited according to the system's framework.
'This won't do, there must be more to this. The void exists outside of time, yet Rubedo found its way into this world. There must be some workaround beyond the system.' The question was how to achieve it. All previous times he gained knowledge outside the confines of the system were either with the help of outer beings already unconstrained by the system or entirely by accident. Yet he knew his budding divinity was there. Omniscience was a wider concept than the mere ultimate skill it was restricted to, but the system kept it constrained nonetheless.
'I guess I will have to try to force it to cooperate.' Momonga poured energy into the skill, keeping the intent to go beyond in his mind and into more. Somehow, he would break past the barrier and find what he needed.
With more and more energy consumed, his frustration slowly but surely grew. As if banging his head against an unbreakable wall, he achieved nothing more than an increasing headache and wasted efforts.
Finally, he ceased the fruitless effort of attempting to go beyond the confines of time and considered his options. Perhaps it was better to use already established paths and expand from there, the information from the research group would perhaps be useful in that regard. After all, there were two time travelers connected to Nazarick already. Both held memories of not only the timeline he wanted to reach but also the person he needed to find.
With that in mind, he settled on using Chloe as an anchor and quickly reached her core within Nazarick. Since it was an invasion of the girl's privacy, he settled on not dwelling on particular moments and going straight for the earliest memories of her being in the current timeline, which were roughly fifteen hundred years ago. What she didn't know wouldn't hurt her.
After shifting memories around, Momonga found the precise point of her traveling through time and as he went past it, Omniscience made a mental doorway to the previous timeline. He could now observe it through the skill, but there was still no way to tangibly interact with it. At least there was some progress, finally, and he could at least locate Rimuru and look for an extraction point to obtain the individual.
'Let's see… I think I could start at the point in which Rimuru appears in the world and go from there. It would be beneficial to understand his character as well.' Momonga reasoned on why he would observe the entire life of an otherworlder-turned-slime. Chloe had already told of the past, however, his main curiosity lay in how the timelines differed and what sort of leader Rimuru was. Even if he failed again and again, there was something to learn, especially for an individual who showed up repeatedly across so many timelines.
Omniscience guided him to the exact point where a football-sized slime popped into existence and started to move around. Soon after orienting itself, the blue creature began to gobble up the hipokute herbs growing in the cave. It also seemed that Rimuru had appeared in the exact spot where Nazarick's entrance was located, interestingly enough. Perhaps the spot had some sort of spatial or magical importance?
For the next three months, little changed. Rimuru just wandered around and ate grass, even crossing back to areas he had already traversed.
'It seems he is very interested in stacking up on resources. A sound tactic considering he is alone.' Momonga mused as he watched the slime at a vastly accelerated speed. Then Rimuru met Veldora. It took Momonga by surprise that the tiny slime consumed the dragon together with the shield to analyze it within himself with the help of a skill. The slime could seemingly consume anything it came across, considering Veldora's past boasting of how strong True Dragons were.
Then came a few events very similar to ones of the current timeline. Rimuru acquired goblins and direwolves one after the other. There were some differences though. First, the slime passed out for three days and it took time for the named creatures to evolve, which likely would be written off to a much smaller magicule pool, perhaps as strong as some kijin.
'Some events are eerily similar. I wonder how much my decisions were influenced by some sort of temporal imprint. I know the names I choose surely were.'
Next was Rimuru visiting Dwargon, where he got into trouble but in the process recruited the same four dwarves to his cause. It was an interesting contrast to how cautious Rimuru was before leaving the cave and then traveling to the dwarven nation with barely any escort, even getting attacked by foolish humans he chose not to kill, likely due to witnesses being present.
Momonga watched Rimuru meeting Shizue with particular interest. This was where he gained a human form that bore a striking resemblance to Buku's for obvious reasons, and considering that Rimuru looked like a child it was easy to see that he could be passed for Buku's son now, Momonga mused.
The next events weren't surprising as well. Rimuru met the six ogres and named them, choosing the names Momonga had instinctively used. Though there were only the main six left and the rest were slaughtered by the orc lord who hadn't appeared in the current timeline, and from the unfolding events Momonga could see why the Dark Sage warned him not to use the Lord title for Geld.
There were a lot of similarities between Rimuru's actions and his, as if the reality itself had strived for a pattern that gets repeated again and again with small but impactful changes, only confirming Momonga's theory that reality itself had pushed him to perform similar actions.
Same as him, the blue slime met Milim after dealing with the orc invasion, though Rimuru decided to spare the enemy, showing a lot more compassion. These actions had worked in his favor thus far, but Momonga wasn't convinced of the validity of such actions in every case.
Even Gazel showed a lot less respect towards Rimuru than to him when the first meeting with the King of Dwargon happened, but the latter brushed it off.
And finally, his actions led to dire consequences. While Rimuru was away, dealing with the five children Shizu had under her care, Falmuth invaded and the first strike was done by the otherworlder trio, which led to the deaths of Shion and hundreds of hobgoblins. And worst of all, the tragedy happened because Rimuru had ordered his subordinates to hold back and avoid harming humans, meaning they were slaughtered with ease. A mistake Momonga was grateful for having never made.
For the first time, Momonga saw Rimuru become genuinely angry. And even in this anger, he still spared Mjurran and the men who protected her after she also aided the enemy. The fact that she was an enslaved tool of Clayman didn't absolve her from the guilt in Momonga's eyes though. He would have understood if Rimuru kept her as a useful tool on a short leash, as the majin was highly skilled and experienced, but the slime just asked to keep up the anti-magic sphere that had aided the enemy and that's it.
'His mindset is too soft for a leader. It surely has its uses, but the enemy should be dealt with accordingly.' Momonga felt a tinge of frustration at what he was seeing.
At least the human army and the three otherworlders weren't getting the same weak-minded treatment as Rimuru personally slaughtered the invading army and captured the king and the court magician while his subordinates dealt with the otherworlders.
This series of events led to Rimuru evolving into a demon lord after collecting enough souls. Momonga carefully observed the slime and particularly the evolving skills to ensure there wasn't anything dangerous that could be used against him if he was taken out of this timeline here. He did acquire an ultimate skill, Beelzebuth, which could absorb both energy and entities and break them down, as a matter of concern, but ultimate skills were no mystery to Momonga now. This skill now housed Veldora and his prison. The skill was eating away at the prison while Rimuru was still evolving and it would take mere hours to break it down completely after the evolution. Momonga also noted that Rimuru had a skill called Great Sage that was very similar to Dark Sage, only it had a voice overlay and more autonomy, making it easier to use. It came as an interesting observation that this skill made thousands of attempts to evolve but wasn't successful.
'Getting another ultimate skill would have surely helped him. Though knowing that he gets killed at some point, it likely does not happen.'
As Rimuru awakened and the harvest festival started, Veldora broke free and helped to resurrect Shion and the deceased goblins as this version of the dragon had also gained Faust and now was able to freely manipulate spiritrons and capture souls still lingering in the isolated area, reviving all of those who had been slain.
'The skill must be connected to Veldora in most, if not all the timelines, that have come before.' Momonga mused while observing the dragon's skills.
As he watched the aftermath of the harvest festival and the conflict with Falmuth, Momonga felt a sudden wave of tiredness approaching. In his attempts at reaching the other timeline, he hadn't paid attention to the ludicrous amounts of energy the endeavor required, and he was running incredibly low.
'I guess I will need to stop and replenish my reserves. It seems even observing Rimuru will take a lot of energy. This begs the question if Nazarick's reserves will be enough to pull him through the timelines once I figure out how to do it. And would it even be worth doing if the price is so high?'
Momogna cut off the connection with the other timeline and slumped down on the throne, feeling Nazarick's presence nearby with a silent question.
'I was not successful in fully breaching the other timeline.'
"Master, the energy you just spent would be enough to create an artificial duplicate of the entity called Rimuru. Perhaps it would be a better option?" Nazarick offered.
"The problem with that idea is that we don't know if Chronoa could tell the difference. If she can, then it will only create more problems," Momonga voiced his fears on why her suggestion might not be the best one.
"Master, it is my duty to inform you that your efforts currently are not cost-effective, and working on means to utterly annihilate Chronoa would be a likely better way to spend the energy. Perhaps experimenting with void and its usage as a means of total entity removal?" Naazarick offered another alternate solution.
Since one of her main duties was to optimize the usage of Nazarick's resources, Momonga couldn't fault her attempts at diverting his attention away from the extremely pricy experimentation. His more pragmatic part wanted to agree and either leave the time experimentation to Veldora and his crew or scrap the whole project altogether considering how expensive it was. Yet there was part of him that wanted to master the ability to manipulate time in case things went south and he would need to retreat to the past and attempt to change things. It was tantalizing to his paranoia, offering another way to literally undo any mistake like a video game save file. And considering how powerful those outer entities were, it could be what gave him enough time to triumph over them if push came to shove.
If Ker succeeded in executing a devastating blow to Nazarick as a whole and killing many of those close to him, the ability to retreat to the past and fix things might become the only option. However, there were the metaphysical implications of timelines and duplicates as Chloe's travel was already proven, problems he wasn't sure he could fix.
"Hmm, I could do some experimentation with void, but I also think there is merit in exploring the options of time travel if for nothing else than extra assurances. Can I rely on you to keep an eye on me next time to ensure I don't waste too much energy?"
"Of course master, you can always rely on me." Nazarick eagerly agreed.
With that, Momonga merged with his sleeping part with the intent to rest an hour and restore at least some of his magicule reserves before the work day started.
Editing by aidan_lo.
Proofreading by aidan_lo, mfkz_rocker, Sluethen, Malguis, clagan, Stac, IAMTHEPLOKOKIOPO, Working Stiff and Alassandro
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