Author Notes: Hello! This is my first story ever and it is also a concept, I can't promise that I will update this story a ton since I am busy with a ton of other IRL-related work.

Boyzilla: Hello, I'm the Beta-Reader for this story. As you might guess with the similar username, Mikezilla is a sibling of mine. I will not write this story but will provide corrections and suggestions, and fact-check the Overlord content. Though I'm not knowledgeable about Reincarnated as a Slime, I'll leave that to him.

Quick Note:
I will not answer "Is he stronger than "Blank" or can he beat "Blank"

Edit 111/3/2021
-Grammar Corrections

Overlord In the world of Reincarnated as a Slime!

Chapter 1: A Sudden Realization

The last few minutes of YGGDRASIL have come. Momonga is outside the Tomb taking in the environment that he and his guildmates once roamed, explored, and built upon. Momonga thinks about how they all made a home, a place to escape reality and the grueling work of life; the NPCs they've constructed spent countless hours detailing and creating them, and the times throughout the game where they all had fun. Momonga stood in the swamplands outside Nazarick with his creation Pandora's Actor, a tall figure, with a neo-nazi sense of style as well as the Area Guardian of Nazarick's treasury. Momonga had a few final thoughts to himself while the servers began their final countdown for the closing of YGGDRASIL.

23:59:35, 36, 37…

Momonga counted down along with the numbers…

23:59:48, 49, 50…

He looked at Pandora's Actor… "I wish I could spend more time here… Dammit! It's not fair… If only it lasted a bit longer..!"

23:59:58, 59-

Momonga closes his eyes in acceptance that YGGDRASIL has come to an end…

00:00:00… 1, 2, 3

Suddenly, Momonga was barraged with sensory information beyond what was feasible. A fresh scent, pleasant and relaxing, and sounds of dripping water from close by. He opens his eyes and sees that he's inside a cavern.

"HUH!" Momonga expressed confusion, "I can smell? Impossible!"

This is an impossibility for YGGDRASIL's VRMMORPG, and the engine was not built for the sensory information of sound and taste.! Momonga tried to check for a menu but couldn't see any visible user interface. He attempted various motions, but nothing seemed to log him out. Of course, this went against cyber law. To entrap people as an offense. And for as shitty as those developers were, they took the threat of law enforcement seriously, not wanting to lose money to a trial if nothing else.

Did this mean that this is no longer YGGDRASIL? Was he trapped in another game? Or by some bizarre, disbelieving circumstance, transported to a real-world?

Momonga looks around and notices that Pandora's Actor is no longer right next to him, seemingly just disappeared.

"What! Where did Pandora's Actor go? Was he perhaps transported to a different location..? Or maybe he didn't come with me at all to this world? I can not worry about this now... I must figure out where I am and if other players are nearby..." Momonga says in a worrying tone of voice.

Momonga starts his exploration of the cavern; he walks past many flowers inside the cavern, which is odd since Blue Planet never did say that flowers grew in no-light conditions. Suddenly, dazzling in rainbow light like magic looked to be illuminated ore along the cavern wall.

He got curious, so he approached the dazzling ore, broke a piece of it off, and started to inspect it, wondering about the properties of the ore.

"Hmm… The ore seems to have a magical complexity to it making it glow this rainbow color. I bet Amanomahitotsu would love to see this material and see its uses for blacksmithing… If only he were around right now…."

Momonga knew how to access his inventory by second nature. A violet void appeared near his hand as he placed the ore inside, mentally noting its storage into his inventory. Then, he remembered that he also held the Staff of Ainz Ooal Gown on hand… However, he wanted to keep it safe from potential PKers, so he stored the Guild Weapon into his inventory, leaving it inside.

Suddenly a gloopy sound bounces off the walls of the cavern, echoing downward towards Momonga. He wonders what it could be and heads off in its direction with cautious proceedings until he spots what appears to be a tiny-sized blue slime within a circular passage.

'Huh? A slime...? A blue slime in YGGDRASIL is a low-level mob… Something like that isn't dangerous to me at the least,' Ainz thinks

Rimuru feels an odd disturbance like something is staring at him, watching him without him noticing, even with him able to sense magicules. He feels like nothing is around him… He turns and suddenly sees an undead with luxurious purple and black robes on with seemingly no dust, a red orb in the center giving off an eerie crimson glow, and matching ruby light which dotted both eyes to give off the sense of dread.

"W-haat! A big skeleton! No! A lich!? Alright, stay calm, maybe he's friendly..!? Yeah, a friendly undead lich! I bet all I need to do is start a conversation! Like I did with Veldora!" Rimuru said in a panicked manner.

Rimuru proceeded with caution, not wanting to provoke the personification of death. "HI! I'm Rimuru, a friendly slime! I'm not a bad slime!" Rimuru says with an energetic tone and friendly manner, using a trademarked quote from a game he knew.

Momonga was slightly shocked at the realization that the slime can speak, his mind raced for answers. Is he a Player or an interactable NPC? Momonga starts to rationalize through many thoughts due to the shock; however, it seems an outside force calmed him down back to logical and reasonable emotions.

"A slime that speaks…." Momonga said out loud. "What type of slime are you? You caught my curiosity. I thought you were just a normal slime, what allows you to speak?" Momonga continued.

'Interesting… I never thought I'd meet a creature that can speak in this world, such as a slime. It could be a specialized type of slime..?' Momonga noted in his mind that some creatures might be able to speak, unlike their YGGDRASIL counterparts.

Rimuru is shocked that the undead actually had a sense of reason, but he was confused by the question of "What allows you to speak" did most monsters not know that they can use 'Magicules' to speak? Or was the undead lich an exception to this rule?

"I think I'm just a normal old slime; I'm shocked you don't already know how we speak. The surrounding 'Magicules' let us convey speech. So anyhow, who are you?" Rimuru says, hoping to get a solid answer from him.

'If things go wrong with this lich, I might have to dash for it! I don't want conflict so early. I don't even have good skills yet! Unless I can manage to use 'Predator' and win the fight early, I don't sense any magicules coming off him. I can't tell his power, can one not have an aptitude for Magicules,' Rimuru thought to himself.

A feminine voice echoed in his head. 'ANSWER: All living things consist of 'Magicules' It must be particular that this one does not due to its unliving status,' Great Sage explained.

'That answers that question, but I need to figure out why he doesn't require 'Magicules' unless he's able to hide it completely?' Rimuru thinks.

Momonga is surprised by the answer, 'What are 'Magicules'? Is it the form of Mana of this world? This will need further investigation, but that is for another time. There is a more important question at hand. How should I answer the tiny-slimes question of "Who are you"?'

He took a few seconds before Momonga thought something up.

'I believe I have an answer; for Pandora's Actor's sake, I will use my Guild's name so that if some of my guildmates happen to be in this world, they may find me." Momonga thinks to himself, concluding on what he shall be called by this tiny slime and others going fourth.

"I am Ainz Ooal Gown! I have been living here for many years. In the deepest parts of the cavern, I heard a sound from a distance, and then I met you." Ainz says to the slime, lying about a bit of his past to not let off suspicious remarks.

'I hope I didn't give off the impression I was lying… It would be a bit tedious to convince him that I was not, so I hope he believes me blatantly.' Ainz thinks to himself.

"Well, it's nice to meet you, Ainz Ooal Gown. If you've lived here in the caverns all this time… What do you say for traveling with me outside of the cavern?" Rimuru says to Ainz.

'Interesting he's offering a journey outside of the cavern. I may be able to get a better perspective on the surroundings and perhaps find Pandora's Actor wherever he has gone." So Ainz ponders how he can find his creation and hopefully increase his information about the world he has found himself in.

And maybe, just perhaps, find his guildmates or Nazarick.

"I would enjoy joining you on your journey; however, I may leave at any time. I have things I want to do myself, and I have someone who I wish to meet. But I'm curious I gave you my name now; what is yours? You must have one?" Ainz replied to the slime.

"I am Rimuru Tempest, a friendly slime, but you can call me Rimuru! Do you want to make the journey towards the exit now?" Rimuru says impatient to leave

"If you want to start our journey to the exit, be my guest," Ainz replied.

And so, Rimuru Tempest and Ainz Ooal Gown set off towards the cavern's exit, it wasn't far from their previous location, however, both of them spotted three humanoid figures. Approaching stealthily, they observed that it was a woman and two other men. The woman seemed to be blonde, with green eyes and holding a staff, while the second man appeared to have a brown and clayish color outfit with brownish hair, and finally the other with a red tie around his hair, making it stick up; he seems to be in a green and brown outfit.

Rimuru hid casually, however, Ainz is not so easily hidden, so Ainz decided to cast [Invisibility] a spell in the lower tier list of his arsenal, which completely hides him as long as nothing interacts with him.

'Hmm, interesting, I wonder who they could be; however [Invisibility] spell is quite a low tier and simple to see through… Since they can't seem to do that, I will give them no mind. For now, I believe exiting the cavern is my priority, and finding Pandora's Actor is my second,' Ainz thinks.

Rimuru and Ainz resume their travel, leaving behind the human party, and find the exit to the cavern. Opening the door, a bright shine of sunlight beams onto them, and they exit the cavern; in front of them instantly is a massive forest full of greenery and a lightly colored blue sky, the sun almost setting creating a light orange on the horizon.

It was a mesmerizing sight for the human known as Satoru Suzuki, the one behind Momonga.

'It is time to make my introduction to this world; even if it is slow, I will spread my name for my friends to find me,' Ainz thought resolutely, prepared to start a new adventure in this unknown world.