Nikolai had some dealings with one Kehari?, who was being hunted by StrangeInfected dragonness called Onya. Nik told her he would try to work out a reverse-infection virus for dealing with Strange on its own grounds. Several days later, he produced the antivirus, but it required testing. Leviathan-Chan and Parity expressed an interest in accompaining him on a tour of Strangewarp.
While down in Strange, Nik got his arm infected. Deep in the Periodical storage, his hand got stuck to a screen and erupted in silver boils, while Nik's mind got taken over by Glossolalia. However, the virus was stopped before total infection, and Nik lost his arm in the process. Leviathan and Parity helped him back to his lab, where he reset safely.
The antiserum tested, it was put to good use the next day. Roque and Onya had a fight, and Nik asked Kehari if he should use the antivirus on Onya herself, instead of on Kehari as a defense, which was the original plan. Nikolai ran off after Onya with a syringe, and managed to stab Onya with it while Roque stalled her. The antivirus did its work, incinerating the Strangevirus, damaging Onyas body but leaving her alive.
But Nikolai didn't leave this encounter unscathed....and in fact, was infected with Strangevirus himself, the same 'Mother' strain that the dragoness had. He's been working in his Lab since, on some sort of project. He has also gone on one excursion to Strangewarp to try and find his missing counterpart (see information on his backup system, which Mother told him was the otter statue in the main square of Strange. This prompted him to cut its head off to search for the uplink implant, then he got into trouble with Slight. Upon being killed and having to respawn, his uplink crystal that was with him was tainted and then exploded.
Shortly after that, Nikolai fled from an [encounter] with Trilogee and ended up resetting his Laboratory, which caused the entire Lab to be infected with the Mother strain.
Sweet William had entered Grey and delivered something of an ultimatum, if a very badly expressed one. The exact quote went something along the lines of 'Give him back to us or we will take our revenge on the unwilling who bears you this speech.' Which might indicate that Strange is willing to kill off the Library's Secretary and do without whatever function he provdes in return for retrieving Nikolai...
His lost clone [was] [found]. Sort of. The attempted capture of Nik by the Strange Medical Corps ended up in minor disaster. Nikolai was taken into Papa Legba, where the SMC used their methods to cure him. It backfired.
During a sudden unexplained two-way link across his remote backup system, Nik was in contact with his lost clone and remembered where it was buried. He took this chance to leap his mind across into the other's brain, escaping disinfection from the SMC, while his old body self-destructed into chaos.
The laboratory, however, was still infected with the Mother strain, and was sealed from entry. It was, incidentally, the only current site of Nikolai's backup data. Which lead to trouble, of course.
Eventually Nikolai remembered a way to keep the Lab from continually respawning off its own backup, which involved destroying the crystal in the Core of the factory. Ojou and System helped him. Meanwhile Mother had lured Trilogee into the lab for some reason, thinking that She could trap the birdgirl and use her as bait for Nikolai. A clone of Nik was also created and inhabited by the Motherstrain.
System had a plan to destroy the lab entirely, pulling it into its home universe Prime and completely converting it into something else. To perform this, System had to go into the lab itself. Ojou helped break down the door, and there was a confrontation with Mother and System. Nikolai, ojou and Trilogee escaped from the lab just in time for System to finish the setting of the markers and completely destroying the inner lab room.
However, Mother had contingincy plans. Enough Strangevirus oozed into the superstructure of the robotic bodies in DarkUnder that housed the lab and Forge to animate it into a walking golem. Though the head (the lab and controlling Motherstrain) had been destroyed, the golem still crashed its way up through Downwarp on its way to Strangewarp. The SMC provided viral disinfection of the local area, then set up a false magic mirror when the titan rampaged into the Transit Nexus. The robot was trapped into a pocket dimension contained by the SMC, who plan to remove the Strange from it. Nik had suggested they convert the Strange to its primordial beginnings--the mirror-stuff.
The final part of the chapter came when Nikolai killed himself once more, by leaping into a frozen lightning bolt in the Cyclotron Forest in Downwarp. Since he had no backup at the time, Trilogee made a kind of rudimentary backup and restored him. This seems to have cleansed him of all final traces of Strangevirus and madness in the same stroke. And he discovered that he's a Spark Gridshaman.