The plague first appeared on the front lines of the Reconquest of Ultramar, precisely on the seventh day of the seventh month of this war's beginning.
Then, overnight, the plague spread throughout Ultramar, raging on every planet.
This disease was named 'Tear plague' by mortal medics and Astartes apothecaries. Its clinical symptoms included an uncontrollable flow of viscous, putrid, mite-infested tears. These tears would glue a person's eyelids shut within seven hours, causing malignant swelling, and with severe pain, patients would almost lose their vision.
This was only the initial symptom; the patient's condition would continue to worsen, and tears would continue to flow, eventually turning into only dark green pus, with the eyeballs subsequently festering, leading to permanent blindness.
Alexander and Sanguinius had warned Guilliman early on that the plague God had set its sights on Ultramar, and it would sooner or later unleash its preferred plague upon the home of the Ultramarines.
Guilliman had prepared thoroughly for this. He organized a large number of mortal medics and Chapter apothecaries, stockpiled a vast quantity of medicines, and developed contingency plans for various types of plagues.
Within the first hour of the plague's outbreak, medics and apothecaries discovered the vector of this virus' spread.
Mites, a very common type of space mite, carried the pathogenic bacteria.
Medics and apothecaries quickly began to act, attempting to cordon off infected areas and clear them, but their methods, relying entirely on human and material universe power, ultimately failed to overcome the Tear plague.
The mites carrying the Tear plague bacteria seemed to possess some Warp properties, appearing to emerge from any place untouched by human sight.
Medics and apothecaries tried every method, but only barely managed to slow down the plague's spread.
After all, Nurgle's plague was by no means something that mortal medical methods could contend with.
Or rather, that they could even slightly suppress Nurgle's plague with only mortal medical methods was in itself not a very scientific matter.
The only good news was that this plague was currently only circulating among mortals; Astartes seemed not to be infected.
Guilliman believed this was entirely due to the effects of the Astartes' modified bodies.
But he was quickly proven wrong, as Belisarius Cawl's Custodes were also not infected by this plague, and only a few cases appeared among the Battle Sisters who came to assist. The mortals led by Sanguinius were also not afflicted by the plague.
And the followers of the Saint Doraemon Sect, like the Custodes, would not be infected or would only experience short-term mild symptoms if infected.
Samantha was one such example.
She was an early infectee, but only experienced tearing, no pus, and quickly recovered on her own.
Many in the Saint Doraemon Sect therefore believed this was Doraemon's blessing.
Some also began to believe that sincere faith could ward off the plague's invasion.
Alexander, however, felt that this was probably some kind of Warp phenomenon: a group of people believed that as long as they faithfully believed in the Emperor or themselves, they would receive protection and not get sick. This idea produced an effect in the Warp, drawing upon the power of the Emperor or themselves, truly making them less susceptible to the plague.
The hum of the land raider echoed through the sky, and the storm rising from the sea made the troop transport sway.
Alexander, sitting beside Guilliman and Ultramarines Second Company Captain Sicarius, rubbed his temples and looked out the window.
The boundless, surging sea stretched to the horizon. The sea was black and green, covered by layers of dark clouds, with tornados occasionally connecting heaven and earth.
The ocean world of Thalassa, now the very front line of the entire battlefield, and one of the areas most severely affected by the Tear plague.
Roboute Guilliman worried about his people; this Primarch, taught by his adoptive parents, was highly humane.
And as a statesman, Roboute Guilliman also knew how much morale he could boost by going among the sick.
Disease is one of the most demoralizing things for warriors; Roboute Guilliman had to appear as invincible as possible.
This was also why they chose a land raider gunship rather than an anywhere door to land on Thalassa.
The anywhere door was too small, only reaching Guilliman's abdomen. Every time he squeezed out of the anywhere door, Alexander couldn't help but laugh.
Sanguinius didn't have this trouble; he could subtly adjust his physique with Psyker power, always appearing perfectly.
Ultramarines Second Company Captain Sicarius, sitting beside Alexander, silently watched the broken rocky islands on the sea outside the window.
Thalassa was Sicarius' hometown, and Sicarius still held the honorary title of Grand Duke of Thalassa. To some extent, Thalassa was his noble fiefdom.
Sicarius had an emotional attachment to this land.
But once it was captured by Chaos, it became a tough nut to crack, and with the spread of the plague, the battle became a stalemate.
Macragge also committed more forces to this planet, and the Cadian 184th Regiment, the only mortal unit equipped with Alexander's tools, also joined in, instantly raising the ferocity of this war by a notch.
This was not to blame Alexander's tools, but mainly to blame...
Suddenly, a thunderous roar like a landslide and tsunami came from outside the window. Alexander and Sicarius both saw an island pulled out of the sea, flying towards another island like a skipping stone under Psyker manipulation.
The islands collided, the seabed groaned, and the Black Legion on both islands were destroyed in this catastrophic scene.
"My island..." Sicarius' whisper sounded beside Alexander.
After the 184th Regiment entered the battle, the situation on Thalassa indeed improved.
For example, there was a small hive city on Thalassa that had been under siege for a long time without falling. Reyna and her 184th Regiment were therefore dispatched there.
Facing this fortress modified by the Iron Warriors, Reyna grabbed a sea island and directly smashed the entire island into the hive city.
Later, Reyna learned that the hive city was Sicarius' childhood home, the family's garrison during his mortal days.
After the land raider tore through the storm layer, it swayed and landed in the Glaudo Valley on Thalassa.
Guilliman and Alexander, escorted by Sicarius, walked out from under the land raider gunship.
An Imperial encampment was set up in this valley, with emergency isolation shelters standing in the rain of Thalassa.
Mortal medics and Astartes apothecaries were moving in and out of the shelters, and occasionally, Eldar could be seen.
Some Eldar in the Death Guard were knowledgeable in medicine; they were assigned to various places to help the Imperium of Man cure the Tear plague.
But even the Eldar could not so quickly cure the new plague cultivated by Nurgle.
Most of these Eldar no longer participated in frontline medical work; they claimed they would find a more efficient way to cure the Tear plague.
Guilliman's face, bathed in the cold rain, twitched as he watched the Eldar pile up a statue of a woman in the corner of the encampment, respectfully praying to the Eldar goddess of life, Isha.
Although he didn't know what Guilliman was thinking, Alexander found this quite reliable.
Isha is a benevolent deity. She is often the first to be infected by Nurgle's new plagues. She drinks Nurgle's freshly brewed concoctions, uses her body to find ways to cure new diseases, and quietly tells mortals in the material universe – not just Eldar, but all races in the galaxy – how to cure them. Many cures for plagues actually come from Isha's whispers.
At least for now, it was more reliable than most methods of apothecaries and mortal medics. In fact, respectfully knocking one's head against Isha might be the most reliable method in the galaxy to cure a new type of plague. Of course, bacterial ones excluded; the most effective method for curing bacterial plagues was in Alexander's possession.
The commander of the encampment quickly stepped forward, attempting to hold an umbrella for the Primarch and Alexander, but Guilliman stopped him.
The mortal commander was too short; even holding the umbrella high, it only reached Guilliman's shoulder.
Guilliman took the black umbrella and held it over himself and Alexander.
"I need to see the patients," the Primarch said to the commander.
They walked together outside the shelters.
Inside the shelters, sobs, wails, and cries of distress continuously emanated, intertwining into a low, oppressive background music that enveloped this world in the rain.
This was only the second day of the plague's appearance. Alexander and Guilliman had arrived here quickly using an anywhere door.
Yet the Tear plague seemed to ignore the limitations of distance in the material universe, spreading directly to all parts of Ultramar.
"Is this plague as strong as you predicted?" Guilliman asked Alexander beside him, his voice deep.
Alexander had previously warned Guilliman that Nurgle might create viruses to infest Macragge.
"I can't say," Alexander shook his head and said.
His understanding of this Tear plague came entirely from the previous life's book, "Confluence: The Rise of the Primarchs."
But that was a campaign book, written very briefly, with many details omitted, and no english translation.
Moreover, Alexander's old english level was as high as Reyna's math level, and that campaign book's phrasing was full of Nottingham dialect, as difficult to read as high gothic.
So Alexander also couldn't determine whether the Tear plague before them was inherently so fierce, or if it was a butterfly effect caused by his arrival.
"The plague God is an excellent bacterial cultivation master. He might have noticed my existence, thereby intensifying the plague's strength."
Alexander said, choosing his words carefully.
"Disease is the creation of the plague God; plague is divine punishment. Only the most ignorant would believe these things."
Guilliman said with a frown:
"But you have forced me to believe that this plague is supernatural, divinely created, profane and unclean, and possibly even demonic."
Although he said this, Guilliman had to believe Alexander's words.
Because this Tear plague came so fiercely, developed so quickly, yet to this day, not a single patient had died directly from the Tear plague.
It was as if an invisible pair of hands skillfully controlled the life of each patient, keeping them at the boundary of being sick but not dead.
Guilliman listened to the weeping inside the armored door, subtly clenching his jaw.
He pushed the door open, but the moment he stepped inside, the sound of crying suddenly disappeared.
The patients, bewildered and delighted, touched their eyelids, finding that the swelling had suddenly vanished, tears no longer flowed, and their blind eyes could see again.
It was as if the arrival of Guilliman and Alexander had driven away all disease and suffering.