Charles saw a vast world inside David's mind, the key being that there were far too many people in this world.
Describing it in a more concrete way, it was a space of strange and marvelous sights, a vast expanse of prairies, valleys, rivers, and lakes, a sky covered in dark clouds, with a solid fortress standing in the distance, and next to it a city, which from afar, looked a bit like Paris, but the people were all scattered across the grassland, reminiscent of a dense flock of sheep.
This was not someone's dream, but rather the structure of the psychic space of the young man named David right in front of him.
If that had been all, it would have been one thing, but it seemed like the crowd had split into two factions and were fighting each other, although Charles couldn't make out what they were arguing about.
The most important piece of information he saw was that the young man named David Haller was a mutant.
Meeting a fellow mutant here was something Charles had not anticipated at all, and his reaction of shock lasted only a moment before he felt a brainwave, slightly weaker than his own, connecting to his brainwave.
Wait, was the other party also a psychic?
In an instant, the two stood up.
A classmate picked up the papers that had fallen on the ground, looking towards the cafeteria windows with some confusion. The windows were closed, so where did that strong gust of wind come from?
The classmates around them also looked around in confusion, feeling as though they had just drunk a strong cup of coffee and suddenly were wide awake.
Noticing that he might cause a commotion, Charles turned his head to look around, then turned to David, whose complexion didn't look too good, and said, "Let's talk outside."
The other's pallid face nodded in agreement.
The moment they stepped out of the cafeteria, a giant phantom descended within David's psychic space, a pair of massive hands seizing the entire world, immobilizing David.
The two arguing groups froze, and turning their heads, they saw only a pair of gigantic blue eyes.
"Tell me what's going on here," Charles's voice echoed in the psychic space, "or I'll find out myself."
There was no room for negotiation, as everyone standing on the grassland found themselves in the grip of a monster, with powerful psychic control abilities that were not only intense but also refined, rendering everyone completely controlled, unable to move or speak.
"Who are you? Where is David?"
Charles was not asking; clearly, he was searching within the psychic space, but then he felt his own psyche become sluggish.
"I'm here."
A voice came from the distant void, but Charles could not see or find him.
"Release me, Charles Xavier," the voice appeared again.
"Who are you?"
"I am called 'Legion.'"
In a flash, Charles's consciousness returned to his body, and he stood frozen in disbelief; he had been kicked out.
He stared dazedly at the young man opposite him, who seemed to take a while to recover. When he did come back to himself, Charles noticed the young man's gaze had changed, becoming sharper.
"Do you know me?" Charles furrowed his brow. When he probed into others' pasts, he usually did so chronologically, starting from the most recent memories. He knew this young man named David Haller had lived in Paris for a long time, but he was kicked out before seeing anything else.
For some reason, reading his mind was very difficult, and Charles silently calculated that if David were an ordinary person, that instant would have been long enough to see all his memories, but unfortunately, he was not, so Charles had seen very little.
"I told you, I am Legion."
"Is that your mutant codename?" Charles decided to probe a little, saying, "I haven't come up with a codename for myself yet. What do you think would be good?"
"Professor X."
"You indeed know me."
The other said nothing, turned, and walked away, with Charles following him. David stopped, turned, and said, "I have to report to my department now. Are you coming with me?"
"Which office are you headed to?"
"Psychiatry 3102."
Charles furrowed his brow again, sizing up David before saying, "So you're also Dr. Schiller's intern? How many hours have you completed?"
"I haven't started yet." David said and then quickly walked towards the elevator.
"Wait for me," Charles quickened his pace, walking shoulder to shoulder with David. "I'm also Dr. Schiller's intern, and I'm sorry for not having told you my real name before. After all, it's quite famous, isn't it?"
"I don't care who you are," he answered.
"But you'll have to wait for me because Dr. Schiller might not be in the office right now, and I'm the only one with a key. But first, I need to go to my mailbox to collect my fellow's manuscript fees."
David's steps halted once more.
"What box number?"
"What?"
"Which mailbox number?" David asked, somewhat impatiently.
"It seems to be 268."
With a swoosh, a brown bag dropped from the sky and landed in Charles's hands. He looked at it and saw the name of his senior brother written on the envelope, as well as the amount of the manuscript fee.
"Aren't you a mind power user?" Charles said incredulously, "You can teleport objects? Or is this a new kind of psychic ability?"
David, clearly exasperated, pursed his lips and strode forward, while Charles, who normally wouldn't be so persistent in asking someone about their abilities since he could usually find out what he wanted to know on his own, trailed behind.
However, the other party was obviously very strong, and prying might be risky and could give away his own secrets instead.
What a hassle, Charles grumbled inwardly. Just arriving in this cosmos and he had already encountered two tough cases, and one was his mentor, the other possibly his senior brother. If this kept up, what would become of his plans?
The two of them reached the exit together, but David suddenly stopped. Charles immediately realized what was happening and said, "You're new here today, right? I could give you a tour of the hospital..."
Another whoosh, and the two of them were instantly in the office. As they landed Dr. Schiller and Charles looked utterly bewildered.
But David stretched out his hand, and a file folder appeared in his grasp, which he then placed on the desk and nodded at Dr. Schiller.
Standing there, Dr. Schiller blinked, still not having caught up with the situation. He looked first at David, then at Charles. They might not have realized it themselves, but their blue eyes were almost identical.
"What's your name?"
"David Haller, I thought he told you," David replied.
Professor X had indeed told Dr. Schiller, but it was in vague terms, mentioning that he had a relative who wished to study there. Dr. Schiller assumed it was some younger member of Professor X's family, possibly someone studying psychology with slightly less ability who couldn't get into the Elders Council Hospital for an internship without going through Professor X.
Of course, it was also likely to be a mutant; Professor X couldn't exactly be considered impartial when dealing with mutants, after all, in his view, they already paid a higher price than others just by growing up, so what's wrong with giving them a few more opportunities?
But Dr. Schiller had not expected that Professor X would send his own son!
Legion!
All Dr. Schiller wanted to do now was sigh.
But then it occurred to him that the one who should be sighing the most wasn't him but should be the young Charles, who must have realized through his mind-reading ability that David was his son, right?
Dr. Schiller suddenly felt a surge of happiness; it wasn't every day that one got to call his own son his senior brother.
Just as Dr. Schiller was about to mock Charles, he became uncertain again, observing Charles's expression and gesture, noting that he seemed unaware that David was his son.
That didn't seem right. From a psychological standpoint, this young Charles seemed quite aggressive and completely ignorant of the principle that one shouldn't rely too heavily on psychic ability. He seemed to be in a state where he thought he could read anyone's mind whenever he wanted.
He hadn't read Dr. Schiller's mind simply because he knew that Dr. Schiller played a crucial role in this cosmos, or maybe Nick Fury had warned him, or perhaps out of respect for the elder Professor X, but this didn't mean he wouldn't do it to someone else.
Charles hadn't accessed David's memories, impossible, unless he just hadn't tried—or someone had stopped him.
But who could stop Professor X?
Even this youthful version of Professor X had virtually no equal in terms of psychic ability, and judging from Charles's expression just now, it seemed he had lost the previous confrontation.
Wait a minute, could it be that personality?
Legion, the result of a certain misadventure of Charles', his very own son, also known as the catalyst for major mutant incidents. His ability was, to put it simply, two words—Schiller.
Of course, that was just a joke. Legion had thousands of personalities, and by that, it's not about traits, but full-fledged personalities.
The main difference between Dr. Schiller and Legion is that Dr. Schiller only consists of personality traits; he's one personality shattered into many pieces, all of which believe they are Dr. Schiller and work together in a way only slightly different from an ordinary person.
But Legion is different. He suffers from genuine Dissociative Identity Disorder, each of his personalities having separate names and identities. Not only do they fail to cooperate, but they also fight, even form alliances and start wars among themselves.
Legion has many personalities. Rakshasa Woman, having ventured deep into his inner world during a certain incident, claimed there were over a thousand, constantly being created, while Legion himself said he had 200 Omega-level Mutant personalities.
He could be labeled an Omega-level Mutant because each of Legion's personalities possesses unique abilities, and even though they exist only in the psychic space, they can use those abilities in the real world.
Dr. Schiller vaguely remembered a personality that could control fire, another that could teleport objects with the mind, one that could absorb another's soul, take control of other people's bodies, and even one that was a giant spider.
But none of these seemed like the personality currently controlling the body, and Legion had one strongest and most mysterious personality—the fifth personality, the God Mutant.
This personality claimed to be Legion, the actual self-consciousness of Legion, and the moniker God Mutant wasn't an exaggeration. The true Legion could whimsically alter reality.
This God Mutant defied all existing mutant evaluation techniques; his power was everything.
During an incident that caused ancient gods like Apocalypse to descend upon the world, in order to fulfill his promise to an ally, Legion erased the god-killing Apocalypse in a single confrontation and reset the entire world.
Afterwards, plots involving this mysterious God Mutant became scarce. There was no discussion of his origin or reinforcement about his strength.
But there was no doubt that in the mutant power hierarchy, only Franklin Richards could prove a match for him. And it was mainly because of this personality that Legion's power rating surpassed most other mutants.
Things were getting troublesome, Dr. Schiller thought. It seems Charles had taken some drastic measure that forced this personality to come out. Now he was going to have to mentor both of these formidable figures.