This is my attempt at Marvel and Overlord Crossover.

Initially, I intend to make Ainz interact with Deadpool, but I decided to abandon that and instead make him interact with Marvel Hero and Villain while trying to find a way home.

In this fanfic I will make some change to Ainz and some of his item he carry:

1. I intent to allow Ainz to learn new stuff outside of his class. I have never been a fan to the whole stuff Ainz and NPC unable to learn a skill from outside their class, it as if saying someone without talent can't learn how to cook for the rest of their lives, not even able to make a sandwich. This is total bullshit, I get that Ainz and NPC supposed to have limitations but this just lame, obviously it will not be like Ainz would be able to learn stuff instantly or anything like that but eventually and surely he is improving and one day master the said skills. In this setting I made Ainz learned [Martial Arts] as Momon, but due to his lack of talent, he only manage to learn the absolute basic...

2. I made some changes for Wish Upon Star, instead of limiting it's used to 3 times only, every 24 hours the ring will recharge by itself and grant Ainz 1 new wish. However, to balance this I made it that the Wish Upon Star ultimately unable to change the rule of reality and the Wish it grants is technically just a much higher-level version of the Magic that already existed in Yggdrasil. Added to that if the wish were so extreme it will demand some MP from the Ainz, and even might cause temporary side effects to him, so Ain would avoid using the item carelessly.

3. Also, I allow Ainz to carry Avarice and Generosity, now listen to me I know that Ainz gives this to Mare to protect him from WI, but in WN Ainz is the one carrying this around, and he fucking need it to use his Red Orb without using a level.

I realize I gave Ainz too much boost here, I originally intended to make number 1 only as the boost but then I realized, man street hero is one thing, but how the heck is he gonna be alive to the like of Hulk and Thor? At first, if we assumed it will be just a one-time encounter Ainz will definitely survive and escape, but then if they have a rematch and the hore goes all out Ainz will likely die, so to avoid instant death I give him an extra boost. However, let me promise you this, Ainz will not one-sidedly beat the Hero, although I can't exactly say the same thing for the villain as no one care if Ainz kills them.

I intent to make Ainz interact with the Villain side as well soon, please make a suggestion of the villains, and also:

- What kind of encounter you like to happen?

- Will they be enemy or ally? or at least neutral?

- Do you want the villain's death or just got beaten up if it becomes a fight?

Anyway, this is all for now, enjoy!

Inside a room, a man is mediating as he floating in the air without anything to pull him up, and this man is the Sorcerer Supreme of Earth Dr. Strange.

Dr. Stephen Strange, once a famous surgeon who sold his skill for a ridiculous price giving him a large amount of money. However, accident made him loses his sense on his arm making him unable to use it for anymore surgery but then he met a certain sorcerer asking him to be his protégé called the Ancient One. His lifestyle changed after that, he who was once a man of science start to dwell in the world of the supernatural, and the once prideful man turned a new leaf and become a humbler man. At the end of his training, his master gives him the title of sorcerer supreme to protect the world from being of another dimension.

It was a hard task, and many times he almost dies, but each time he manages to come up on top, and eventually even take many student under him. Some turned rogue while some went beyond him, soon one of those pupils of his will take on his mantel but for now he is still the Sorcerer Supreme of this realm.

"Stephen, the guest has arrived."

Suddenly Wong, the friend of Dr. Strange and his closest ally call out to him

"…Let him enter."

Wong nodded and one more left the room, on the other hand, Strange decided to fix posture preparing for his meeting with the new guest.

He been expecting this guest, for quiets sometime.

Way even before the guest intent to come to his place and asked for an appointment, Strange had been aware of him. After all, it is not everyday someone coming to this world from entirely different reality.

Suddenly the door of his room opened once more, and this time Wong entered the room while being followed by a man wearing a dark rob with a hood covering his faces.

"…Dr. Stephen Strange, thank you so much for accepting my request to meet today. My name is Ainz Ooal Gown, I have come to request your help to get me home."

"I'm aware of that. I've been watching you for some time after all…"

"…"

The figures called Ainz show no sign of surprise to the statement, this is obviously the figure in front of him clearly dwell in the art of Magic as well and should have noticed Strange try to watch his actions. There was even time Strange magic to watch him countered showing a clear sign that the figures aware of his existent. However, it seems Ainz has no intention to bother to discuss that matter here, so Strange immediately continued the conversation...

"Well, then Ainz— You don't mind me calling you that right?"

"Yes, that is fine."

"Alright, then Ainz. I had been aware that you come from different reality than ours, you carry air that completely different from the native of this world or any of the dimension I'm aware off. However, what I don't understand is how you arrive in our world exactly?"

This is what Strange had been questioned to himself it had been sometime that he is aware someone entered this world coming from the outside. Problem he didn't know exactly when and how? It was almost as if he popped out of nowhere making him fail to detect him for quiets sometime…

He was hoping the figures in front of him could answer this for him, but unfortunately the figures shook his head…

"My apologies, I'm not sure exactly how I get here. No, I guess it was incorrect I'm aware I was send here using some form of magic by a certain enemy of mine from my original world, but how exactly I'm not sure. The magic this person used is a bit unique, the users in old world can be counted by fingers and thus I lacked the knowledge of the exact method."

"…I see, that is unfortunates."

"Then, Dr. Strange, would you mind answering my question this time."

Suddenly Ainz asked that to him, but Strange himself doesn't exactly mind…

"… I will hear it…"

"…Then, my question is about the whole dimensional travel. I only manage to know about you from the underworld information, but it seems that you are capable of doing dimensional travel is that true?"

"Indeed, but my dimensional travel is a bit different from what you imagined. While I can't say anything about yours, our reality had been connected to many other realms we slightly different rules than ours. However, all those realms are not exactly separate, it was all ultimately come from exact same root. Your world on the other hand, from what I can tell most likely an entirely different reality all together. If I had to put it in a much simpler analogy, all the dimensions I visited all this time are all leaf that come from the same tree, while yours are leaf that grow from an entirely different tree. Which is why most likely this ability of mine is not exactly what you seek."

"…I see."

After hearing all this, Ainz shows a clear dejection. While Ainz can't exactly tell his expression due to the hood, he can tell that from his body languages alone. However, he can't fully blame Ainz for this. Most likely Ainz had come here to seek the help of Dr. Strange to send him to his home world after hearing about his ability but unfortunately Strange unable to help Ainz, at least not with his current knowledges…

"…I apologize if I have given you false hope…"

"No, while it is true that I'm slightly disappointed. I had thought of the possibility that you will not be able to send me back."

"There is no need to get pessimistic yet, while I cannot guarantee it will bear fruit I will speak this matter to the rest of my colleagues if you don't mind me revealing your identity to them of course. Obviously, I will make sure the person I spoke to able to keep secrets so they don't tell anyone you can't trust..."

"?"

Hearing Strange words Ainz, show a slight confusion and then asked…

"While, I definitely appreciate that, why would you do that for me? This is not something I can brag about, but right now I have nothing of value I can give you. My transfer was extremely sudden, and thus I fail to bring anything that will worthy of your attention…"

"…It is not like I expected anything from you in return, no I guess I do want something in return. To be more specific in exchange for my cooperation I would like that during your stay in this world you would not harm anyone in this world unless it was defend yourselves."

"Why would you bother to ask that? Both of us should aware that you could easily eliminate if you deem it necessary. You're way above me in the art of magic..."

This is true.

Ainz, is an awfully strong magic user both Wong and Strange are aware of this fact just at a glance, but it is also true Strange is above him. If it had been a normal Sorcerer, Ainz most likely would be able to kill them almost instantly without much trouble regardless of their numbers, that just how ridiculous Ainz is. However, as Sorcerer Supreme Strange are drawing power from Vishanti the trio God who had been bestowing power to all those who held the title Sorcerer Supreme.

The power Strange possessed are no longer that of a human, and very well entered the realm of the Deities. Regardless how powerful Ainz is if that come to fight in direct combat Ainz chance of winning would almost be non-existent…

"…It is true that I can do that, but I would prefer if it don't come to that. However, if I must give out a much more concrete reason it would be to avoid a similar event to happen in the futures."

"…What do you mean?"

"As I said before the dimension I had visited so far are all come from the exact same tree, the situation where we have visitor coming from an entirely different tree were a first for myself. However, if it happened once there is no guarantee it would not happen again in the future, which is why I showed an interest on helping you out. If we succeeded to sent you back then, the next time similar events happen once more, myself or my protégé would be able to take care of it immediately."

"…I see."

"So, what do you say? Will you accept the condition I set out?"

"…If the condition is just to not harm anyone in this world during my stay unless it is to defense myself, I would gladly accept it. It is not like I would like to cause some trouble while in this world."

"Alright, then we got ourselves a deal."

Strange then make some sort of hand gestures and then some light flew out and then Talisman came from out of nowhere…

"What is that?"

"…Some form tracking devices as well a communication means for us. As long as you carry it I will be able to know where you're and able to contact you."

Ainz slightly suspicious, at first after analyzing using [Greater Appraisal] the talisman by himself he found out that the talisman function are exactly as stated. So, he reached out to it…

"Understood I will always carry this with me."

"Then, I guess that is all from me. Is there anything else you want to ask Ainz?"

"No."

"I see. Then, I believe our discussion for today should be finish. Would you be staying for some more chats?"

"Thank you, but I must refuse the offer. While I would like talking more here, I still have something I need to do."

"I see, then Wong…"

"Understood, Mr. Ainz this way…"

Wong opened to the door for Ainz and lead the way out of the room…

Ainz immediately response, and took a turn and walk to the door

But, then Strange suddenly called out to Ainz one last time…

"Ah, I almost forgot, Ainz. This is only if you don't mind, but before you leave Ainz would you mind show us your faces?"

"—…"

For a moment there is a slight silent in the air, but then the figure called Ainz sighed and then removed his hood showing his faces. The face under the hood were that of a human, but without skin or flesh or simply put jut a skeleton with a mysterious red light in the place where eye should be. Biologically speaking such a being shouldn't be alive at all, and this look alone enough to cause fear for the civilian. However, Wong and Strange have met many scarier creatures in their life, they didn't even flinch when they see his faces.

"I see so you're indeed not human after all."

"You're not surprised?"

"Hardly, I have seen creatures much scarier than you could possibly imagine, However, the fact that you asked something like that did you by chance thinking both me and Wong would be scared or something?"

"Indeed, I have been in this world for sometime but as human in this world seems to not have seen my species before once time someone seen my faces and freaked out so I forced to hypnotize the person to forget about the event. Since then I've avoided to show my faces, or if I'm outside I will cast some illusion or even shapeshift myself…"

"In that case why do you show us your faces?"

"Please consider it a sign of trust from me. Isn't that why you asked to see my faces in the first places?"

Well, Ainz hit the nail there.

It might not be much, but for Strange working with someone whose face he had never seen isn't exactl comfortable. This especially true because Ainz had blocked his attempt to watch him using magic, sure he might be able to see it if he used a much powerful spell or just use Eye of Agimoto, but he is not so desperate to do that either. So, instead, he asked to see Ainz's faces directly…

"Well, then I appreciate the trust you gave me. Still, you sure quite a unique species may I assume everyone from your world has similar look such as you? Or at least the one from your home planet?"

"No, while there are indeed creatures that look like me, my species but one of the many species in that world. My world is a bit unique, in our home planet there are more than few thousand of species that have high level of intelligence and each have their own cultures. Some of it even looked exactly like the human on this planet."

Strange nodded to this.

"I see…"

"Is that all?"

"Yes…"

"Well, then I will take my leave for real this time. Hope to see you again Dr. Strange."

"Yes."

This time Ainz leaves the room, and soon after Strange left alone once more in his room and he returns to his meditation…

0000

5 Minutes later

Not long after leaving the room, and lead Ainz to the outside of the building, Wong returned once more to Strange rooms once more…

"Stephen, we need to talk…"

"Do you want to talk about why I cooperate with Ainz so easily?"

"Yes, the way I see it that Ainz have an evil nature. No, I guess saying he is evil a bit wrong I do sense some good in him, but he is not exactly a good person either. From the way I can feel it, Ainz probably had killed several millions of lives."

"Indeed, I agree to that. While I can't enter his mind due to some sort of mental protection he has, I'm still able to sense his nature, your estimation about him is most likely correct."

"Then, why?"

"Why? Then, Wong I asked you should I just kill him on the spot, even though he never attacked anyone here?"

"… No, that…"

"It is true his nature is evil, but the way I see it he has a certain level of intelligence and flexibility to adapt to his situation, he is not the type to do evil without reason. For all, we know his world might be in constant wars and thus he forced to be evil and take many lives. In that case, we have no right to judge him for his nature."

Unknown to Wong and Strange while it is true that Ainz world is in war the one cause that war was exactly Ainz due to him wanting to unite all the nation in New World under his banner to protect Nazarick. Simply put Ainz, was the source of the war and trouble in that world, alhough to defend himself even without Ainz interference the species of that world are already killing each other and even eat other sentient life form without guilt. If anything, while his method is cruel he does produce result by letting those who lives under him lived prosperity…

"Also, as I said before but the case where people from another reality like him had never happened. So, I indeed hoping to be able to fix this situation so in the future if something similar happened we can fix it immediately. Obviously, there is one more reason…"

"What do you mean?"

"Simply put is the unknown nature of his existents. As someone that come from the outsides he should by nature followed different set of rules from our worlds, such a being entered our world what do you think will happen?"

"Wouldn't his body adapt to this world to suit his needs?"

"It is a possibility, but the way I see it might be the other way around. The world would try to adapt to Ainz existents and as a result, it will be contaminated and adapt a new set of rules that never exist in this world. Effectively changing the world as we know it, and we will not know whether the changes will be good or not…"

"I-Is that possible?"

Wong, started to feel sweat behind his neck…

Would a single person really able to affect the whole world just simply existing? Such a thing sounds so far fetched, but at the same time, the lack of sample doesn't allow him to deny it either.

"I'm not sure, but assuming this is true then even if I kill him there is no guarantee the contamination would be stopped as his soul itself would still reside in this world. In that case, to eliminate any chances, I would rather find a way to send him back. Are you convinced?"

"…Yes."

It is true that if Strange theory is correct then just for save measures it will be better to send Ainz home…

After that Wong excused himself from Strange's room, and the both of them returned to their activity…

This is how the hero of Marvel first interacted with Ainz and whether or not this leads to a better future or not, no one knows it yet.