(General POV)
Location the Nethervoid-Castle Neo Oblivion/The Throne Room
Laharl was just returning to the throne room from the Dinning Room, having finished having a feast with his wives as he was enjoying the aftermath of the meal, and he watched the succubi handmaidens working all around the throne room, cleaning and organizing everything in the room.
Smiling at the site, the Dark One decided to leave the castle and wonder around his domain it has been a long time since he had done that.
So he stretched and cracked his kinks as he started to leave the throne room and, in turn the castle and once he did he used his [Physical Shift] skill to sprout his wings and take flight across the Nethervoid.
Flying over the Infernal Black Jungle, sensing the dark shamans below performing even spotting some of his hell spires guarded by his lesser daemons, the knightmares he also traveled to Charybdis with the stalkers drinking from the ambrossia pool, and later he went and observed the Observer Hive with his second greater beasts of Carnage all floating through and from the former Greenskin sacred relic turned into a spawning area for his daemons.
After observing these landmarks, he flew away to the north, seeing several of his shrines scattered all over the violet ground, eventually reaching the Valley of Countless Spikes, the territory of his fanatical and highly mutated cultists upon seeing him flying through the skies they started praising and praying to him, making him stronger and amused in the few moments to fly across the valley, he reached Kiira's Palace of Depravity overflowing with succubi and poor souls that the succubi have taken from Kolbaline to torture and entertain themselves even from the skies the Dark One could not only sense the pain of these mortals but hear their cries of agony.
Laharl laughed happily he flapped in the place, looking over everything of the Nethervoid, he decided to fly towards the newest addition to his realm but he then sensed the growing disturbance in Warp, looking up at his maroon sky, using his divine senses to feel the growing surge of another power in the Warp, which only meant one thing...Nurgle.
While Nurgle was still clearly weaker than him or Khorne at the moment, him being able to sense the future Plague God meant that he is getting stronger and closer to his birth while he still didn't know when his new brother would be finally born and face him in battle, just sensing the new Chaos God's power meant that their meeting at the battlefield was getting closer, plus truth be told he was curious in how much GW was underestimating the horrors that is Nurgle's Garden, while he wasn't a huge Nurgle player in his past life, he was still a fan of the Plague God.
Laharl smiled excitedly of the prospect of crossing the Plague Garden and facing Father Nurgle was pumping the Dark One.
So instead of going to the Shi'lanorai Mountains, the Dark One decided to go visit his seer, the elder daemon Ba'al Allseer, so he can not only carefully scry when Nurgle will be born, but also more future events like Tzeentch and of the damn Anathema progress on the Earth.
While Laharl could only guess that humanity was entering the plague ages, but still not the age of the Black Plague, which Nurgle original birth from but with the divergence from the original timeline with him and Khorne attacking and slaughtering all the eldars, and with the orkz helping the overall massacre which was spreading plague and sickness across the galaxy.
With his plans decided, he headed towards Ba'al Allseer's Abyssal Library.
Location the Nethervoid edge/Floating Isle the Abyssal Library
Flying through the Nethervoid, eventually, he arrived at the giant cloister belonging to his first son Ba'al Allseer, just all the times he has visited the cloister before the Abyssal Library was covered by he saw the cloister being covered by violet thorns marooned colored vines stretch, coil, and spread across this cloister, but the largest amount of this thorn vines were in their own cluster in a massive dome of thorns, he had to admit aside from Nidhog that slept underneath Lake Styx they're all quite eccentric in the construction of their cloister territories.
After admiring Ba'al's cloister for a few more moments, the Dark One he landed at the entrance of the thorn vines cover over the Abyssal Library and made his way in.
Location the depths of the Abyssal Library the Chamber of Prophecies
Laharl entered the Abyssal Library, the eldritch library that would make Tzeentch and his followers mouth water upon seeing it horrific majesty, it has like always expanded in size with Void Wraiths and Spectral Heralds maintaining the shelves, books, tomes, and grimoires created by Ba'al and his Scriptors have recorded from his visions in the "Web of Time" the lesser and high-daemons welcome him and showed their Dark God respectful reverence and admiration as he made his way down to the basement aka the Forbidden Sections of the Abyssal Library.
The dark, depressing, and gloomy atmosphere of the basement levels where all the more dangerous works of the Great Seer are kept, along with all predictions that have been derailed like the early rise of the Eldar Aspects, that tome involving that prophecy must be somewhere in the Forbidden Sections, but Laharl was in a hurry so like many times before he took the quickest option to the bottom chamber, jumping over the edge of the bridges connecting the various floating cloisters of book shelves.
After falling for a great height, Laharl reached the deepest floor within the Abyssal Library, causing a loud and great bang sound from him crash landing on the obsidian stone floor of the level.
As the Dark One stood up without any issue he looked around to confirm he reached his destination and he saw gigantic altar/personal library section belonging to Ba'al signaling that he was in the right level, just like the last two times he went to the Abyssal Library he followed the source of power emanating from the beholder daemon, Ba'al further in.
Walking for a few moment he once again arrived in the Chamber of Prophecies, he stood there looking at Ba'al at the other edge of the chamber, as his Elder Daemon was is in his usual trance all his thirteen eyes have been rolled on the back of his head, his six wings were spread releasing white feathers as they are caught in the psychic storm produced by the beholder Elder Daemon, and lighting shots out from various part of Ba'al as the thirteen Scriptors did as their tasked to record all that Ba'al scrys in the Web of Time.
No matter how many times the Dark One comes to see his Elder Daemon, Ba'al he was always impressed and also compares what he's seeing it just like what the Lords of Change do to Kairos Fateweaver.
Since the Dark One wasn't in any hurry, this time he simply walked over to a pile of books, tomes, and scrolls laying next to a large shelf overflowing with books and sat on them like a makeshift throne.
There, Laharl waited as Ba'al Allseer was scrying and speaking about a great shift in the Web of Time, which interested the Dark Harbinger and gained his full undivided attention...
(Ba'al Allseer POV)
While scrying through the web, as I spoke, revealing all I see...
"I saw much from the rise of the Plague Lord along with the two other Chaos Gods, the fall of the Eldar, the priumphant rouse of power and followed by the deepest fall of the humans, the greentide that run rampant across the stars, the return of ancient metal men from tombs of old, and much more...
But this isn't the source of divergence, it was heralded by the sound of a bell...rung thirteen times and from a great rip countless rats, death machines, vile creatures twisted from rats, being lead by daemons I've and non-other have seen before all rallying under the banner of a horned rat...
This new tide of Chaos shall ravish the galaxy drowing in it in a vermintide that will consume human, ork, eldar, kin (squats), necron, and much more...
All of this shall come to pass when the Dark One travels into a world so ancient...connected to Chaos but separated from the whole Materium..."
(General POV)
As Ba'al finished his latest prophetic speech, what the beholder daemon said really pleased the Dark Harbinger, he obtained much more than he originally came for seems that at the end of the second chapter of the Great Game, he goes to the Old World to face and make the great Horned Rat join the pantheon of Chaos, as a fellow brother just like he planned to do once Nurgle is defeated.
He then noticed that Ba'al started to exit out his trance, and immediately, his thirteen eyes turned towards the Carnage God, closing his eyes and making a makeshift bow towards Laharl he welcomed him once more to his Abyssal Library.
Laharl closed his own eyes as he chuckled and stood up from his makeshift chair, walking forward to the Great Seer he spoke, "My elder daemon, Ba'al Allseer I need you to once again dive into the Web and tell me of Nurgle's birth...and of the Anathema." understanding his dark master Ba'al returned to his trance state.
Just like that, Laharl waited for Ba'al to tell him what he needed, turning his head slightly Laharl saw that the Scriptors were writing like crazy at the prospect of more knowledge of the timeline, this made the Dark One shake his head and sigh, he wondered if his void wraiths were actually Pink Horrors in disguise if it wasn't because Tzeentch isn't born yet...