Indeed, it was Robbins who suddenly, for reasons unknown, kidnapped Sandman, locked him up, and it even seemed like he hypnotized him, ultimately leading to Sandman's loss of control.
So, it seems that the source should still be Robbins; however, the question remains whether it was Robbins who kidnapped Sandman, or Sandman who kidnapped Robbins—no one knows.
Possibly, in their respective memories, the incident is completely reversed, and since the contamination itself can affect the mind, they might be utterly convinced of their own memories, although their memories have already been altered.
In other words, it's also possible that Sandman kidnapped Robbins, contaminated him, then let him go, pretending to be the kidnapped one, so both of them are equally suspect.
But on deeper reflection, Shiller felt something was off. In fact, the incident between Robbins and Sandman was not the earliest; the earliest should have been Mysterio changing identities and forming a team.
Or to put it chronologically, the earliest incident was Mysterio's perfect identity change, and two people were involved – Mysterio and Sophia, meaning they both are equally suspect as well.
According to Shiller's own observations, it should have been Sophia manipulating Mysterio, but it's also hard to say whether they were both acting in concert, or if they, too, failed to realize there was something wrong with their memories.
But after much thought, Shiller still felt something was wrong; he believed he had overlooked something or missed some detail and could not simply pin the suspicion on these four individuals.
If direct deduction won't work, then it must be reasoned inversely; Shiller roughly guessed who the contaminant came from, but if it really was that piece of crap, then how did it get here?
If he could figure that out, he could probably deduce who it first came into contact with, thereby revealing the source of the contamination.
Shiller recalled a previously hair-raising but ultimately safe incursion. Godspeed Reaper from DC invaded here, carrying a Laughing Egg. Fortunately, at that time, the Legion was at the peak of their powers, intercepted by a temporally capable persona within the Legion, and Mad Laugh's plot ultimately did not succeed.
Could this be a repeat of the same trick? Probably not that simple; Mad Laugh surely knows by now that invading here through the stream of time is nearly impossible, and due to copyright issues, he couldn't possibly make a public appearance here, otherwise he could never withstand OAA.
This means his method of entry had to be both secure and secret, but after considering everything that had happened during this period, Shiller found no possible loophole for his entry.
Having been strategizing in Marvel for so long, Shiller was confident; since his arrival here, there hadn't been many events beyond his expectations, most of which he had perfectly resolved, further strengthening his grasp over the cosmos. Thinking about finding a loophole now was already too late.
Wait, what if it's not about now?
What if Mad Laugh had invaded here much earlier than anyone could have imagined? What if Mad Laugh had invaded Marvel even before he appeared in DC?
Suddenly, Shiller realized that all of this might just be a trap set by Mad Laugh.
He could have appeared before Shiller earlier, because after all, he had dealt with Dr. Anatoli before and for some reason knew about Anatoli's relationship with Shiller; he could have shown up even before Gotham was saved.
But he didn't. He waited until much later and didn't sneak in for a surprise attack; instead, he chose to send a letter first, flamboyantly announcing his arrival.
Mad Laugh indeed has this penchant for popping champagne at the start, but that is the Mad Laugh from the comics.
The Mad Laugh Shiller knew had been hunted by Anatoli and had survived, even developing an egg-laying ability from who-knows-where, and even sniffed out the relationship between Anatoli and Shiller. If he relied solely on the comic book version of Mad Laugh's abilities to speculate, he might miss something.
Mad Laugh used a cognitive trap.
Now appearing in DC, people would think, like other supervillains, he has just made his entry. But what if he has been stirring up trouble behind the scenes for a long time? What if he had already reached the edge of the great world, explored the existence of Marvel, and even prepared for it there?
Some might say, if that's the case, then why would he need Godspeed Reaper carrying the Laughing Egg to invade?
But Shiller thinks this is critical because it fully demonstrates Mad Laugh's dangerous nature but hides his deeper threats. It lets people know he has the ability to invade, but makes them believe he has just come to invade, leading everyone into a cognitive trap—that he has never invaded before.
While the reality may be just the opposite.
Shiller isn't completely sure how effective the invincible foresight ability from the comics is in reality, and if there could be a logical reason for it; but even putting aside this invincible foresight, after all, he is Batman, and he has the qualities a Batman should have.
Every universe's Batman is an extremely clever deceiver, adept at all sorts of blind eye techniques, psychological inductions, and diverting attention, so even if Mad Laugh only had the basic attributes of an ordinary Batman, he could still create such a trap.
So, assuming Mad Laugh did indeed come to Marvel before his appearance in DC, how did he get here?
Passing through the Origin Wall seems a bit unrealistic, Shiller believed, because the two universes are not neighbors; it's not as if one can just cross that wall and directly reach the neighbor. The distance between these two worlds is infinite, requiring special methods to confront each other.
With God and Lucifer present, the likelihood of Mad Laugh mastering this method and successfully implementing it isn't very high—he likely wouldn't choose such a strenuous method.
That left only one possibility: the real breakthrough establishing a connection between the DC and Marvel was the Battleworld created by Shiller.
In this realm, characters from two different vast worlds could interact without any barriers.
Indeed, the first group that entered the Battleworld had undergone rigorous screening, with everything from their physiological to psychological aspects thoroughly examined. Shiller had even been cautious of the possibility that someone might harbor a Laughing Egg inside them, like Bruce, so he searched through every aspect of their psychic worlds without any issues.
But that was the past. Now, Shiller had discovered an undetectable form of contamination, both mentally and physically, and it was very likely a trick by the Mad Laugh, which also meant that there might have been an oversight in the initial checks.
This contagion was too mysterious; it couldn't be turned up in a psychic search or seen in a physical examination. The only way to remove it was for the contaminated person to die and then be revived, making it difficult for the technology of the Battleworld of that time to detect it.
This oversight had given the Mad Laugh the opportunity to infiltrate.
Shiller had no choice but to delve deeper into his reasoning. As early as when Arrogant and Joker Jack had entered Bruce's psychic world and excavated that egg, the misguidance might have already begun.
After discovering that egg, Shiller realized that the Mad Laugh might exist in this way, which could make him overlook other methods the Mad Laugh might have.
One could even say the misguidance had been present since Shiller began reading comics because as everyone knows, the Mad Laugh was adept at anticipating moves, so what Shiller was most cautious about was the anticipation, and all the preparations made by Arrogant were basically to guard against anticipation.
No, that's not right, Shiller then thought. For the Mad Laugh, if Shiller only knew about his ability to anticipate, that was perfect because it could significantly paralyze Shiller's judgment.
For the Mad Laugh, then, it was best if the egg remained undiscovered because it would keep Shiller believing that the Mad Laugh only had the ability to anticipate and no other capabilities.
The egg was a reminder.
Going back to its origin, how was the egg produced?
According to Lucifer, the original Shiller came to Gotham with immense power and obliterated the Source of the Curse in one fell swoop, turning these dangerous elements into eggs, including the almost unsolvable villains, the Mad Laugh and Doomsday.
It might be because in the setting of the world, these two elements were unsolvable, but the energy possessed by the original Shiller was enough to destroy everything. These two rules clashed, causing a deadlock. Thus, they compromised with each other, existing in a harmless yet undead form.
This meant that it was in fact due to the original Shiller that the egg appeared; this reminder was left by the original.
Then, if we assume that the original Shiller was actually Anatoli, this means that this reminder was left by Anatoli, hoping that Shiller would not be fooled by the character set of the Mad Laugh in the comics and would understand earlier that the Mad Laugh might have other abilities.
Did Anatoli know then that Shiller would come?
If we follow the previous speculation, the sequence of worlds Anatoli experienced should be: the world he was born in — the DC Universe — the reality world where Shiller was thrown.
This means that at the stage of the DC Universe, Anatoli originally wouldn't have known about Shiller.
If he did know, then it might not be a coincidence that he went to the reality world; he might have specifically sought out Shiller.
But this isn't surprising, after all, he had dealings with Lucifer, and Lucifer knew the truth. Anatoli might have known in the DC Universe about the soul of this little boy who had ties with Lucifer, whose soul was thrown into a certain universe and was the original owner of this body that would eventually return.
So, he laid out plans in advance, prepared, and after collecting enough energy, used an explosion to abscond and erase his identity, leaving the energy in his body and the perfect layout for the arriving Shiller, whom he had personally mentored.
This explained a long-standing puzzle for Shiller: when he was at the institute, there were many recreational activities available, and he could have engaged in normal activities like watching cartoons or reading books, but Anatoli brought him a lot of comics, letting Shiller read them whenever he had nothing else to do.
This was the main reason Shiller could remember every major American comic book character. At that time, in the institute, he read all the comics that Anatoli brought him. He might not have read every single one, but he had pretty much covered most of them.
Combined with his superb memory, even minor characters like Little Calamity, who appeared only once or twice, could be pulled from the depths of his memory whenever he wished.
But there was one issue in all this—since Anatoli had such great capabilities, why didn't he come himself? Why did he have to go through Shiller?
Was there something special about himself? Could it really be just because he had formed a bond with Lucifer?
Shiller always felt it wasn't that simple; there might be deeper secrets within him that were the real motive behind everything Anatoli did. But at the moment, there was insufficient evidence to speculate further.
Moreover, the priority wasn't to research himself but to investigate how exactly the Mad Laugh used the Battleworld to contaminate others and what impact it had on the entire Marvel World.
At the time, the scale of the Battleworld wasn't particularly large, and not many Marvel characters entered it. Although some came from other universes, since the trouble erupted in Shiller's universe, he had to prepare for the worst-case scenario—some superhero from this universe might have been contaminated at that time.