Does Mephisto understand love? Of course not. Devils can understand human emotions, but they comprehend them empirically—because they've lived long enough and seen many people act driven by emotion, they can roughly estimate the behavioral logic driven by human feelings. In simple terms, it's behavioral analysis.
Demon Gods have desires, but no emotions. Their joy comes from desires being satisfied, their anger from desires being unfulfilled. These emotions cannot be said to be true feelings, much less can they have emotional motivation. They will never do anything beyond satisfying their desires, like sacrificing for love; they have no experience with this and cannot comprehend it.
So, what would happen if a Demon God understood love? Then they would actually no longer be considered a Demon God but would be closer to a human. This is not devolution but true evolution. Love would bring them closer to God.
But, as Hanix said, what makes a person strong will also make them weak. If a devil understands love, they possess all kinds of human emotions. They will better understand humans and know how to tempt and drive them, which will make them stronger. However, love also creates weaknesses, making them want to give to others, even to the point of sacrifice. Their behavioral logic becomes more complex, with more points of vulnerability.
It can't be said that this holds no temptation for Mephisto, because clearly, as Strange grows up and humanity's development in the universe improves, Mephisto is becoming increasingly insignificant, with fewer opportunities to cause trouble on Earth.
It is imaginable that one day, humanity will completely bypass the middleman of the Demon God and directly derive power from the rules of the universe. By then, all Demon Gods will become a dish, Mephisto included.
The so-called poverty inspires change, and it's the same for Mephisto. He feels his desires are increasingly unmet and thus increasingly wants to become stronger, to restore past glory.
However, like electronic life forms, Demon Gods are distant from God. Their lower bound is high, but their upper bound is low. Mephisto is omnipotent only in his hell dimension; once he leaves, he cannot even affect the laws of the universe. Gaining an advantage before humanity now is a fantasy.
But how to break through the shackles of talent? Mephisto has the answer in his heart. To be closer to God, one must be closer to His creations, and God's proudest creation is humanity.
The talent of humanity has no upper limit. Even without mentioning mutants, there are countless people like Stark, who, without any inherent physical advantages, can glimpse the truths of the universe and alter its laws solely with wisdom.
Devils are greedy; of course, they want such talent. But they also understand, to become human, they must possess emotions, and those who are emotionally rich must be burdened by those feelings. Is it really worth it?
Mephisto looks at the baby in Sarah's arms, and he can somewhat guess why this is the case. Heart of Darkness appears to be the embodiment of sin, but he is very close to humans; otherwise, even the Supreme Magician wouldn't be able to tell them apart once he became human. He possesses real emotions, just like humans.
Heart of Darkness once asked Mephisto if he had any other relatives. Mephisto, of course, told him no, because at that time, even Mephisto couldn't have imagined that Sarah would come back to life and they could reunite.
However, after knowing this woman's existence, Mephisto knew his son longed for his love, and he wanted to return to his mother's embrace. He was overwhelmed by this feeling, which is why he ended up in his current state.
This is the best proof that even the strong must be burdened by their strength. The human part of Blake allowed him to successfully infiltrate Earth, even to the point that Strange had no reason to act against him. Yet, it also made him yearn for maternal love, bringing him back to his mother's embrace, completely disrupting Mephisto's plan.
"This is not a good place to talk," Mephisto said. He glanced around; the others were fine, but Hanix made him wary. Mephisto had dealt with this witch before, but evidently didn't gain anything favorable. He didn't want her to see his vulnerabilities.
"Come with me," Greed said. He led Mephisto out the east door to the edge of a cliff. Meanwhile, Chris hurriedly ran to the far east side of the second floor, standing at the corridor window looking down. Though unable to hear their conversation here, fortunately, Chris could read lips.
"You've pursued quite a few people," Greed said, looking at Mephisto. "You transform into their favorite form, appearing in their dreams, tempting them to fall. But if you think carefully, there are bound to be a few cases where you failed. How did they resist the temptation? Was it really due to devout belief?"
Mephisto fell into deep thought. His life was indeed long, and he had accumulated too many memories. He searched through the fragments of his memory based on Greed's description. The vast majority of these seductions succeeded, if not leading to fall, at least causing some wavering. Yet among thousands of successful cases, there were indeed a few complete failures.
These examples were separated by long periods, sometimes even hundreds or thousands of years. Mephisto had never compared them together, but now that he did, a certain pattern quietly emerged.
Those who completely resisted temptation and even directly expelled him, were not successful individuals in the sociological sense—not outstanding politicians or successful businessmen. Most were ordinary people, some even living at the bottom.
These struggling ordinary people should have been easier for devils to tempt, as they had gained so little and should have been willing to agree to a devil's terms for a better life. But the fact was the complete opposite; most of the failures came from these exceedingly ordinary individuals.
"There was a farmer's wife," Mephisto began. "I turned into the likeness of her late husband, and she indeed fell in love with me. We spent a beautiful year or so together on the farm. But when I wanted her to offer her clever yet frail youngest son's soul as a sacrifice to me, without hesitation, she stabbed me with a pitchfork."
"There was a young man, and I transformed into his favorite beautiful and romantic lover, spending a spring night with him. He loved me deeply, but when the enemy set foot on his homeland, he gave me a hug and a kiss and resolutely left, dying on the battlefield, never to return."
"There was an old man, and I turned into the image of his most cherished first love. He treated me as an angel sent by God to save him. But when I wanted him to give up his research and leave with me, he chose to refuse."
"They weren't any big shots," Mephisto said, "one was a countryman who had never been to the city, the other a boy born in a remote area, a chemistry teacher who taught all his life. They all rejected me, completely wasting my efforts."
"Do you see? This is the difference between humans and devils. To gain power, you can use any means, constantly scheming to tempt humans to satisfy your own desires. But the emotions humans use to resist temptation are nobler than their instinctual desires—a love for family, for country, for career. These are the treasures the Creator gave them, allowing them as mortals to defeat devils and become stronger than you."
"If I wanted to have emotions, what should I do?" Mephisto paused and added, "I've lived so many years, but if ever I were moved by human emotions for even a moment, I wouldn't still just be a devil now. I can't understand, let alone empathize."
"That's normal," Greed said, "not to mention you, even among humans, there are those without emotions. Even if you completely mirrored the human body structure, with a brain replicated down to the tiniest detail, it doesn't mean you'd have empathy.
"But I always advocate that the healing of the mind starts from the imitation of behavior. If you want to become a healthy person, start by imitating healthy people.
"Someone who likes anxiety should pretend to be a happy-go-lucky person, playing the role of someone who carefree and goes with the flow. At a random moment on a random day, go out and do something without a plan, empty your mind, and if unexpected things happen, just go with the flow.
"Someone feeling depressed should pretend to be an ambitious person, someone with countless things to do every day. Fill up your schedule and complete the tasks on your agenda, and through means like sharing photos, pretend you get a great sense of accomplishment from completing a task.
"Even if you know inside these are all fake, you must convince yourself, immerse yourself in it, and keep persuading yourself that this is who you are. Attribute all physical and mental pain to not satisfying the 'fake persona's' needs and desires, thus further urging yourself to behave like that fake persona.
"It's somewhat similar to correcting a crooked sapling. As long as you consistently bend the sapling growing to the right towards the left, even if it can't be completely straightened, it can still have some effect. It's considered a relatively effective psychological therapy when you don't have the ability to change the surrounding environment."
Mephisto nodded, seemingly comprehending something. He said, "Then who do you think I should play?"
"You have too many issues." Greed spread his hands, "Indulging in desires, being unscrupulous in matters, cunning and insidious, full of bad intentions..."
"You're talking, so can you avoid personal attacks?"
"Does a devil mind this? Isn't calling you insidious a compliment?"
"Ha, I've already started acting," Mephisto said, "From now on, I'm the embodiment of justice. Don't say I'm evil."
"It's not about what you say, but what you do," Greed said, "It's best to find a reliable reference for this kind of thing, to avoid learning it wrong."
Mephisto nodded again and said, "Let me think... How about Captain America? He's the embodiment of justice in human hearts, very popular among you. I should be able to imitate him, right?"
"You started with the hardest one, are you sure?"
"I'm Mephisto," Mephisto snorted and said, "Even if we take a step back, a seasoned devil like me can't go and imitate a confused young one in their twenties, right?"
"Alright, you can give it a try," Greed continued, "But he's not in the manor right now, he's in Hampton below, you can go find him."
Mephisto left without saying much. Greed yawned, preparing to catch up on sleep, but before returning to his room, he informed Sarah that he had dealt with Mephisto, and that guy wouldn't be bothering Sarah and her son anytime soon.
Returning to his room, Greed had just laid down when Steve called. Captain America's tone was filled with anger and shock: "What the hell! Shiller! How is there another me here?!!"