Before beginning, a few definitions:

PK= Player Killer (normally Players that target other Players)

Devs= Developers

MOB= Typically used in MMORPG games and stands for attackable non-playing objects. Usually monsters.

Dungeon= In RPG terminology it is a closed environment usually having many enemies and treasures.

Raid= is an engagement involving a large organized group of players typically set in a dungeon and involving difficult bosses.

The Raid Boss is extremely difficult in comparison to other types of bosses in the game, being the master of the dungeon and the last line of defense that protects its treasure. It's a boss specially designed to fight a large number of players.

Prologue: Birth of the Raid Boss

The first thing Harry saw upon opening his eyes was a clear, blue sky. He could feel grass underneath him, and a soft breeze that was comfortably cool. He let out a soft sigh, silently thankful that it seemed to be a calm, quiet day.

…Yet another world, eh?

Considering there were times when Harry landed in the middle of bloody war, this peaceful scenario was certainly welcome. Lying over the ground without a care in the world, he simply admired the sky and the calm chirping of birds for a moment until he felt it had been long enough.

Rising from the ground so he was in a sitting position, he looked around lazily in a seemingly uncaring manner. At first glance, there was nothing but trees surrounding him, the only thing different from the green scenery were the rocks at his back, leading up to what appeared to be a mountain.

No immediate threats at least.

Standing up in a relaxed manner, he stretched until he felt his back and shoulders pop satisfactorily, releasing a contented sigh.

Merlin, world-traveling is so tiresome. The body is always tense upon arriving.

Rolling his shoulders experimentally, he was surprised to feel the usual lethargy fade away as if it never was. It was a little too fast for it to be normal, considering previous travels always took from two to five days.

Maybe this world's gravity was lighter? Although there was quite a huge amount of magic in this world as well; Harry could feel it practically oozing from the ground… the latter was probably the reason he had recovered so soon. He could feel his magical core latching at the magic on his environment, making up for the loss the travel to a new World always caused.

Mentally shrugging, he made a mental note to experiment with it later and started to walk in a seemingly random direction. First things first, he needed to know what kind of world this was. No matter the amount of magic or magical creatures it held, if this world didn't have a race intelligent enough to be civilized, he was leaving.

Using sensorial magic, he searched for any living forces within the vicinity, only finding it after half an hour of mindless walking. It was a small group that was situated to the east, where at least ten creatures seemed to be resting, judging by the lack of movement.

Harry should be able to catch up with them in no time.

Once he was closer, Harry could see the party of humanoid creatures. Their equipment varied a lot, even from such a long distance; he could distinguish gear that resembled a cleric, a swordsman, a lancer, an archer, a wizard….

…even from such a long distance?

Why was his vision better?

On normal circumstances, Harry would have needed to enhance his vision magically in order to be able to at least distinguish their forms as humanoids. But he was capable to see not only their silhouettes but their gears, even the runes and other small details that covered most of them.

How odd.

Harry frowned, closing his eyes as he focused on himself instead of in his surroundings.

His magical core felt… different, much stronger than usual. The magic of this world seemed to be attracted to him as well, since he could feel it surrounding him as if he were perpetually walking around steam. It was only noticeable if he focused on it however.

This world automatically enhanced any magical beings? It had never happened before, so Harry wasn't sure, but that was his best bet at the moment.

After hesitating for a short moment, he decided to approach them. He needed information from this world, and the group of people over there was his best option right now.

Once Harry was closer to them however, he was forced to jump sideways to avoid a rain of magical arrows. The items impaled the ground mercilessly, just over the spot he had been at.

"Over there!" a male shout was heard, which was immediately followed by another rain of arrows, this time accompanied by harmful spells and long-ranged weapons.

Tsk. Why were they attacking without confirming who he was?

Quickly deciding that they may stop upon seeing his human appearance, Harry ran towards them, not too close to be in their range of attack, but enough to be seen. He could have apparated, but he had felt reluctant about showing his own magic so soon. What if this world didn't have teleportation magic? He didn't want to drag attention to himself, not so soon.

Wanting to avoid that, he decided to go the old fashioned way, but was surprised to see he arrived at his intended destination in nothing but seconds. It had been so fast he might as well have apparated.

…Why was he faster than usual? Physical attributes were automatically enhanced by magic as well?

The party of ten was still looking at the direction he had come from, and stayed like that for another few seconds before they all turned at the same time, almost completely synchronized.

"What the—? How did it—?!" the male lancer babbled, before assuming an attack position once more. Harry raised his hands in an unthreateningly manner, but that only caused some of them to shout out random variations of "It's preparing an attack!" before reassuming the battle.

…Well damn it.

If he had to beat them up before they would be willing to listen, then so be it.

Determining the best way would be to knock them out, he summoned his elder wand and fired a couple of stunning spells in quick succession. It was just a warning, so there was no need to incapacitate all of them—

Immediately after however, Harry froze in shock, at the same time shouts of "Orazeq no!" and "Dian just died!" resounded around him.

What the—?! Why did a stunning spell kill them?!

Even odder, the corpses of the fallen had disappeared in a colorful light immediately after, leaving behind only a random piece of equipment.

"What the hell! This is supposed to be a Level 30 zone!"

"Shitty devs!"

"Retreat! It will wipe us out otherwise!"

"No shit Sherlock!"

A chorus of shouts and bickering followed the unexpected situation. Harry cursed under his breath, before trying to speak once more.

"I'm sorry, I didn't mean to—" Harry started to say, but his words didn't seem to reach them. The battle resumed once more, but this time Harry simply evaded their attacks, focusing solely on defense.

Their movements felt oddly slow; it was highly unusual considering he was a wizard, not a warrior. He had some practice in close-range battles sure, but he would always be better on those large-ranged, if simply because that was his specialty.

Still, the swords of the warrior and the sharp end of the lance didn't hit him. It was almost as if the world around him was moving in slow motion. He was thankful for it, since it made evading much easier, so Harry simply added this fact to the mental list of things he would need to investigate later on.

Sighing at the current situation, he mentally cursed at his carelessness.

He had just killed two of their comrades; it was obvious they weren't going to listen. He should retreat and search for another—

His line of thought was cut abruptly, and for the second time in the last few minutes, he tensed in surprise. Distracted, one of the arrows almost hit him, but he managed to evade it at the last moment.

The people he had accidentally killed, was back!

Without any sign of injury, as if nothing had happened. Their comrades, who had taken the fallen pieces of equipment, simply tossed it to them as if it was a common occurrence, and they quickly placed them on before joining the battle once again.

A thousand theories ran through his head, but all of them pointed at the same direction. Reluctant to believe it, he lost focus on the battle he was participating in, evading only with automatic motions. The only reason he had yet to be hit at this point was due to his, now enhanced for some reason, reflexes.

Could it be that this world… allowed resurrection?

"It's not attacking! We may be able to defeat it!" cried the one that appeared to be the leader of this group.

"Come on everyone, let's do the usual!" the female cleric cheered, which was immediately followed by a chorus of "Yeah!" from the rest of the humanoid team.

A few other words were exchanged, but Harry was not hearing them anymore.

A world that allowed resurrection was against Death's law. So why was this different? Why was this world an exception to this unbreakable rule?

Harry made his resolve, tightening the hold on his wand as he changed his position. The party in front of him seemed to notice this movement, since their attacks stopped abruptly for a moment. It was nothing but a small pause in the battle, but it brought with it a huge change.

Harry's role as Master of Death would not let him leave without investigating this at depth.

Having reached this conclusion, Harry mentally apologized for what he needed to do, before starting to fight back. He made sure to kill only one at the time, and to receive a few attacks from the remaining nine members so the enemy would not lose their fighting spirit. Harry also made sure to study the battlefield at all times to determine from where the resurrected person was coming from.

Slowly, he redirected the battle towards the direction the resurrection seemed to be taking place at. It took around ten deaths, which meant that all the group had died at least once, but Harry was eventually able to reach the resurrection point.

A bright circle was drawn in the ground, with glowing runes he had never seen before. He witnessed as the lancer appeared directly in it before the man immediately jumped out and resumed the battle. Harry tested it a couple more times, taking out the cleric and the archer, just to see if it applied to the other members as well. Once they appeared on that same circle however, his theory was confirmed, so he determined the experiment had been going on for long enough.

He needed to summon Death and study that mechanism at once. The last thing the universe needed was a world where death was not present.

Mentally apologizing once more, Harry killed them all at the same time, in quick succession. The whole party appeared over the huge runic circle, which had extended automatically in order to accommodate all of them, and Harry immediately wiped the whole team once more.

And again.

And again…

"What the hell! Why the sudden change—?" the warrior began to say, before disappearing in a bright light as he died once more.

"We were fighting against it just fine one moment ago—" the lancer shouted in confusion, before following the warrior's fate.

"Could it be this thing is a Zone Boss?!" the female cleric exclaimed, which made Harry pause for a second before continuing his attack. He had never heard that term before…

"More like a goddamn Raid Boss!"

"What would a Raid Boss be doing in the middle of—"

"This is not a dungeon goddammit—"

"Fucking devs!"

Again and again they appeared, and Harry terminated them just as quickly. He paid attention to their parting words, but the terms they were using were unknown to him.

Curiously, after the 30th death or so, the whole party did not appear anymore. Instead of ten members, there were only seven left. After another round of death, only five came back, then two, and finally none.

It made Harry sigh in relief, since the conclusion of this experiment was evident. The resurrection had a limited amount of times it could be used.

It seemed to vary according to the strength of the individual, since those Harry identified as stronger lasted more times than the others, but it seemed permanent death was still possible in this world, it just was harder to reach.

The situation was not nearly as bad then.

Still, the circle with runes had yet to disappear, so Harry couldn't count it as completely good. It most likely meant that this specific group was not the only one that could resurrect…

Passing a hand through his hair tiredly, he called for his old friend to come. The immortal entity appeared in front of him instantly, this time having chosen to appear as a female, hooded figure, and lasted the whole amount of three seconds before the eternal being started to laugh at him.

…what was so funny?

In the meantime, the defeated players complained about the unfairness of it all in Yggdrasil's fan-made community, telling to anyone willing to listen how their whole party had been wiped out by a random Raid Boss, which had come absolutely out of nowhere.

"The damn thing continued to kill us until we had no levels left! I refuse to level up from the beginning all over again, I'm quitting!"

"Me too! Damn thing ruined the game!"

"Fucking devs!"

"LOL there's no way that's true"

"You were just PKed massively, eh?"

"It was not a player!"

"Sure bruh, whatever you say"

"Just a strong MOB?"

"No! The zone was for level 30 monsters! That thing WAS NOT!"

"Maybe there is a dungeon nearby and the Raid Boss is unusually guarding the entrance?"

Comments like these could be read all over the website, even more so when, after some time, more parties claimed to have encountered this particularly difficult 'Raid Boss' (although some insisted on calling it a 'Zone-migrating MOB Boss'). As such, as more battles were described, the story inevitably changed over time.

More details were added, describing how this out-of-the-norm 'Raid Boss' seemed to actually keep the equipment their avatars dropped upon dying, and how the players that had insisted on fighting to try to get their gear back always ended up dying many times consecutively.

There were also stories of how this Raid Boss didn't have a pre-defined set of attacks, nor did it seem to follow a pattern. If they didn't know any better, the players would say that this particular enemy actually adapted to the battlefield, according to the situation at hand.

But that was impossible. No Non-player character could be created to fight that way, there had to be a limit.

The rumors twisted continuously, but at least half of the community agreed that the 'Raid Boss' existed, and that it was so strong that if a party weaker than Level 100 fought against him, it would be wiped out without trace.

The Raid Boss, odd as it sounded, seemed specialized on PK. This enemy would secure the resurrection point and wait for his enemies to resurrect… so even after the members of the affected party re-spawned, this dangerous foe was on them again, PKing them again and again. Eventually, this would force the party to disband in order to escape from their repeated harassment.

These stories eventually reached a particular player. The person in question hummed interestedly, tapping their fingers over the wood of the desk where the screen was placed at.

"It sounds fake but… the rumors say that defeating that Raid Boss unlocks a special feature in the game. It doesn't have a defined dungeon though, so we would need chase it out… ah, but it may be worth it!"

With that excited phrase, the player nodded with determination, before connecting to let his friends know about these rumors. If anything, he was sure Momonga and Ulbert would agree!

AUTHOR NOTE:

Welp, I'm sorry for writing this instead of working on my other fics! This is the last one, I swear (?) If anything, the fault lies on Rosedraquia, seeing their cool OP!Harry made me want to try it out! Bless you dear author, why is your writing so cool?!

For those that don't know of it, I really recommend you Rosedraquia's story "Master of Monsters" which is a X-over with Overlord and Harry Potter available in AO3. OP!Harry is the best! and their writing is really cool!

This is the prologue with only 3K words = 8 pages in Word, but man do I want to write the next chapters.

Btw, don't worry about Harry having Nazarik as an enemy, not going to happen. It's going to be explained in next chapter tho haha

Anyways, thanks for reading and hope you like it, see ya' around!