Far off from the Alolan region, in what was nicknamed the 'Glacial Region' a research station had closed down for the night. The staff there had all mostly gone to bed, leaving only a few to continue the night shift. The station was built to study the shifting star fields that were far off from their planet, as well as to study pokémon in a region where trainers had never been before. It was interesting… Some of the pokémon were the same as their regional cousins you would find anywhere. Calm, skittish, but ultimately just living life. Then there were some who was far more violent and aggressive, often attacking other pokémon or hunting them for what seemed like pleasure. The weirdest thing however, was that a small pokémon called Snom was apparently the alpha predator of this region. Even pokémon such as Abomasnow and Houndfrost did their best to stay out of Snom's path. One of the scientists had found a Snom outside the base one night, and now it was the team's pet. No one knew how this thing could be such a threat, as Snom didn't even appear to have teeth. Regardless, the team had been studying the nature of wild pokémon for the past four years, with this year being their final year before their study was completed.

Walking into the security room, a scientist sat down and passed a coffee to her friend. The security guard nodded her thanks, and they sat in silence, looking up at the night sky.

"They said that Rayquaza showed up here once, do you know if that's true?" She finally asked.

"I wasn't here, but yeah. That was real." The security guard nodded. "It was about sixteen years ago, in July. They said that some sort of meteor crashed out there, and then Rayquaza and some other weird pokémon began clashing. After that… they disappeared."

"Huh."

"Yeah… If Professor Watanabe was as serious as he was the last time I asked, I'm willing to believe that it happened."

"What made it appear?"

"Well, they claim that the meteor that crashed here was some sort of thing from another dimension, and Rayquaza apparently believed it to be a threat."

The scientist was about to ask another question, when a screen nearby started beeping, as if warning them pre-emptively.

"Did a Houndfrost break in by accident again?"

"No… no, it's just a weather warning." The security guard shook her head. "It's weird though, they said there wouldn't be any wind toni-"

Before she could finish her sentence, something rocketed past the window, seeming like a flying green snake. This creature was moving with a mixture of anger, as if some sort of challenger intruded on its territory, and the fear of an animal that knew a new Alpha had arrived. Neither woman got a good look at it, and before they could look to see it's retreating form, a mountain of snow that was pulled along this creature's return collapsed onto the room's window, darkening the small room.

"Wait. What was… was that…!?"

"Get Professor Watanabe on the phone! NOW!"

Somewhere on the other side of the planet, a small bush began rustling as if some pokémon was digging around in it. This was because there was a pokémon digging around in it looking for berries. However, the pokémon stopped and looked up when it felt a presence that made it… frightened if it was honest. So, it did what it did when I was scared. Curl up in a ball and not make a sound.

"I am not here to harm you." Mewtwo spoke in as calm a tone as he could, but one that also had sincerity and urgency in it. "This will be easier if you come out."

Slowly, a small shrub-like pokémon slowly walked out, looking up at Mewtwo.

"W..what's wrong?" Shaymin asked.

"Something's happened in the Alola region, some… THING has appeared, we don't know what it is. But Giratina believes it could either be a threat, or an ally."

"Okay… and you want me to…?"

"Out of all the pokémon I've met, there's one I believe would be the most helpful in this scenario." Mewtwo stated. "He and I are not on good terms as of late, and he most likely wouldn't listen to me. We need you to go talk with him, and bring him to the Alola region.

"Ooh! Can I bring Miss Cynthia too!?" Shaymin asked hopefully. Mewtwo cracked the faintest of smirks.

"Indeed, Giratina believes she may be of use as well." Mewtwo nodded. There was a bright flash of light, and Shaymin had changed into his flight form.

"Where should we meet?" He asked.

"Go to the Isle of Melemele, if I am not there when you arrive, go on without me."

"What are you doing?" Shaymin asked, curiously.

"If this being is who Giratina believes he is, we are going to need all the help we can get in stopping him." Mewtwo said gravely. Shaymin nodded in understanding.

All across the mountain town, the ground shook aggressively as heavy footsteps impacted the ground, one after another. Slowly making his way across lava bed towards the ocean, Groudon looked on in disdain. Slowly entering the cave that would lead downwards, the volcanic, kaiju-like pokémon remained deep in thought. After a short walk, but one which felt much longer, he emerged at the lava bed where he was once awoken. He paused, knowing this was going to be… annoying. He looked at a large rock, then kicked it into the nearby opening, watching it sink into the water below. After a few moments, a large, fish-like creature appeared.

"What do you want?" He drawled.

"Something's wrong." Groudon stated. "The others are gathering, they've asked we be there."

"Don't care." Kyogre replied dismissively, preparing to go back underwater.

"This isn't about us, this isn't about them it's apparently about some sort of outer-dimensional threat that will hunt us down and kill us one-by-one." Groudon stated flatly, which got the sea pokémon to pause.

"Bah." He finally said. "Shaymin was always easily frightened. If some sort of new pokémon seeks to destroy us, let him come and face the fury of the wate-"

"This was Giratina who summoned us." Groudon cut him off. "And this thing is believed to be human."

Kyogre remained silent, listening in disbelief at what he was told.

"Where do we meet?" He asked.

"The Alola Region, a small island no trainers know about." Groudon answered, his tone becoming more… awkward. "And, there is one other thing…"

"What?"

"I need a ride."

On Akala Island, the Doom Slayer was sitting on the beach, watching Cubone and this 'Ash' kids' Pikachu running back and forth, seemingly playing tag or something.

"So, if you're from another world what got you sent here?" Ash asked, this being the one question no one had seemed to have remembered to ask yet. However, this did seem to noticeably agitate the Slayer. Before anyone could apologize, VEGA spoke up.

"During our time on the UAC Station, the only other survivor was an android named Doctor Samuel Hayden." The A.I. spoke. "He was once human, but had his consciousness transferred into a cybernetic body. He was the head of the station, and one of the originators of the Argent Energy project. His goals were noble, but his actions… less so."

"So, was he helping you during the invasion?" Hau asked.

"Somewhat." VEGA replied. "We were in a position when if we didn't work together, we would both die. Although the Slayer decided that he wasn't in favor of allowing Dr. Hayden to continue with his experiments. After Oliva Peirce opened the portal to Hell, the Slayer had to re-enter hell to close the portal. After that, Hayden…"

The A.I. trailed off, as if unsure what exactly happened next.

"We were teleported away, and ended up here."

"But, if Hayden needed you to stop the world from being destroyed, why would he want to get rid of you?" Ash asked.

"It probably had something to do with the billions of dollars' worth of property and equipment damage the Slayer inflicted upon the base." VEGA answered honestly. The Slayer shrugged clearly saying 'I don't care'.

"Um, I don't mean to ask a rude question… but is it possible that those demon things might end up here?" Lillie asked, feeling unnerved about the possibility of demonic invasion.

"Unless there exists a pokémon who can open a portal to the afterlife, and would willingly do so for an extended period of time, the demons would be unable to enter your world."

"Oh, good." Lillie said relieved.

"So, what's next for you?" Kukui asked with a raised brow. "Do you have a way home?"

"Well, the Slayer was wondering if there was anyone in this world who knows anything about inter-dimensional travel." VEGA remarked.

There was silence as they thought it over, then Hau's eyes lit up.

"Hey, do you think the Aether Science Foundation might be able to help?" He asked.

"Eh… maybe?" Kukui replied with a shrug. "They were more about helping pokémon, I doubt they'd be able to open a portal across dimensions."

"Well, as it stands, the Slayer will most likely travel this island until he is able to find a way home." VEGA stated.

"Hey, I'm not sure if anyone's told you about them yet, but if you're gonna be traveling around, people might ask if you're doing the Island Trials." Hau spoke up again, as if realizing something. "I take it you don't know what they are, right?"

"Island Trials? Like those weird Runes?" The Slayer wondered before shaking his head.

"Right, so all the young trainers have to travel across the islands, there's challenges for the trainers to go through." Hau explained. "They've gotta battle different Trial Captains before reaching the final trial."

"And these Island Trials are some sort of rite of passage?" VEGA asked.

"Kinda, yeah." Hau nodded.

"…I don't say this to be insensitive, but I highly doubt the Slayer will take part in these trials." Vega finally spoke. His sincerity did get a laugh from the group.

"We weren't expecting him to." Kukui stated with a smirk. "But, in all seriousness, I gotta advise him against carrying his weapons around in the open. There's a lot of people who will probably call the cops on you because of that, guns aren't really common here…"

"Understood." VEGA replied. "The Slayer only uses his weaponry when there is a clear demonic threat."

"Good to know."

"Or if he is bored and decides to go skeet shooting."

"Wait."

"He's not someone I picture skeet shooting…" Hau muttered confused. In response the Slayer pulled out his heavy assault rifle and affixed a scope to it. Before anyone could stop him, he took aim, and shot a coconut roughly a hundred feet away. There was silence, then screams of terror.

"That may not have been a good idea." VEGA remarked.

"Yeah, no. It wasn't!" Kukui shouted in disbelief. "You could've hit someone!"

"But the Slayer didn't. But still, that is what you would call a 'dick move'."

The Doom Slayer paused, thinking things over and ignoring the horrified looks he was getting.

"…wait. Wasn't there also the Dimensional Research Lab in Heahea city?" Ash asked, having remembered something. This DID get a reaction from the Doom Slayer, who snapped to attention, looking to Ash. He didn't need VEGA to say what he was thinking. However, the look on Kukui's face was him practically begging Ash not to say anything. After a few moments of silence, the Slayer go up and began to walk away, Cubone following along.

"Burnet…" Kukui said, his face draining of all colour. "We need to stop him, NOW."

"Professor, what can we do?" Hau asked, a tone of realism clear in his voice.

"….right." Kukui muttered. "Uh… you guys… you guys… agh… I DUNNO!?" He shouted. "Just… get the cops, or something! I gotta call Burnet!"

Kukui took off running in the direction the Slayer had gone, and the trio looked to one another.

"You don't think he'd hurt anyone, right?" Lillie asked. "They… they don't have any way of opening a portal to the afterlife, right?"

"Yeah, they're entirely about monitoring weather and space." Ash nodded. "Still, we need to do something."

"Okay… look." Hau said, trying to rationalize things. "This is probably the only thing they've gotten in ages, right? So, the Slayer shows up, realizes there's nothing, then leaves. Right?"

"I hope…" Lillie frowned nervously.

Over at the DRL, the staff was working feverishly as some massive anomaly had materialized hours ago, and had caused violent, unpredictable changes to the atmosphere and weather, and then just as quickly, it stopped. But then mere minutes later, the tides had become unmatched, and there were reports of extreme heat, followed by extreme cold, and then followed by large thunderstorms.

"C'mon people! What was that thing!?" Professor Burnet called, looking over the charts and readings. "Have we ever seen anything like this before?!"

"I mean… not in real life." One of them muttered, getting the Professor's attention.

"Not in real life?" She asked, confused.

"Well, some of these patterns seem familiar to what would happen when some of the ancient pokémon appeared." He explained. "Thunder, fire, ice, waves, changes to the atmosphere from above…"

"You think there's some sort of convergence of legendary pokémon?" Professor Burnet asked, her eyes widening hopefully.

"I can't say." He shook his head. "And besides, wasn't there some sort of weird event yesterday? Some sort of being from another world?"

"I dunno." The professor shook her head with a frown.

As the Doom Slayer made his way across town, he wasn't paying attention to anyone around him. There was something about 'Dimensional Research' that really set him off. He knew what could happen if they messed with portals and other dimensions, it would end with everyone dead. He didn't know what they were using the research for, but he knew what humans were capable of, and what they'd do with the knowledge. Furthermore, if they could help him get back home, that'd be helpful as well.

"Slayer, I do not know what your plan is once you arrive, but I implore you to remember. These people are humans who have most likely met any sort of demonic presence." VEGA stated as the warrior from hell kept walking, seeing a large white building coming up. As he kept walking, he didn't notice a beige cat pokémon do a double-take as he passed by.

"W..what is t'at?" He muttered before following him at a distance.

The Doom Slayer was on a one-track mind, and ignored the looks he was getting, especially by a man with blue hair, and a woman with ling pinkish-red hair.

"So… that's the newcomer they were talking about…" The woman said, raising a brow. "Well, what's the plan?"

"He's just a man in armour, I think CarnIvine would be able to knock him out, then we take the armour, and whatever pokémon he has. The boss will appreciate it."

As the Slayer entered the DRL, the secretary didn't seem to notice him at first, but gasped audibly when she looked up, feeling horrified by what she was seeing.

"Hello. We are looking for the Dimensional Research Lab." VEGA said as the Slayer looked down at the secretary.

"Um… T..Th…third floor." She stammered, pointing upwards. The Slayer nodded and walked into the elevator and pressed '3F'.

Nothing happened.

Looking up, the Doom Slayer saw 'Weight Maximum Exceeded'.

"Cu?" Cubone said with a tilted head. The Slayer left the elevator and headed to the door marked 'stairs.

"Hello?" Professor Burnet said, answering her phone.

"Burn?! Are you okay!?"

"Whoa, hold on. What's wrong Kukui?" She asked, hearing the panicked tone of her husband. "Uh, yeah. I'm okay…"

"Listen. You and everyone there need to get out NOW. There's some sort of other-dimensional guy from hell who's on his way to the lab."

"Whoa. What?" Burnet blinked. "Honey, slow down! What are you talking about!?"

Without warning, the doors were thrown open, slamming into the walls adjacent to them. Everyone froze in shock and turned to face whoever appeared. However, no one knew how to react as the Doom Slayer entered. He looked around and felt… underwhelmed. There wasn't a giant portal base, there wasn't pipes of this world's argent energy, everyone seemed normal.

"Uh…" Burnet began.

"Cubone?" The pokémon on the Slayers' shoulder chirped.

"Greetings." VEGA broke the ice. "I am VEGA, I am the Doom Slayer's assistant."

"The Doom Slayer?" Professor Burnet blinked. "Uh, can we help you with something?"

"Well, we were wondering if this lab had the technology to open a portal to the dimension from which the Slayer came." VEGA asked.

"No, not really." Burnet shook her head. "This place is meant to observe the effects of pokémon that may appear form another dimension, not to open holes to those dimensions."

The angered and imposing body langauge of the slayer suddenly changed to a 'Wait. Seriously?' body langauge. He seemed to be realizing that he had made some sort of mistake…

"Are you the figure everyone was talking about the other day? The guy who apparently came from another dimension?"

"Yes." VEGA answered. "The Doom Slayer is not from this earth."

There was silence, then multiple objects hit the floor as everyone went slack-jaw. Burnet's eyes widened and seemed to sparkle almost childishly in excitement.

"REALLY!?" She suddenly shouted, surprising everyone present, as she was normally the calmest and collected of them all. "Oh, wow. I didn't mean to do that… Sorry. I just, I just have a bunch of questions about that. I mean, I'm sorry…"

"The Slayer and I have some questions concerning your studies, and we would be willing to answer your questions in exchange for information."

"Yeah, of course." Burnet nodded with a grin, motioning to the tale. The slayer nodded and sat across from the professor. The Cubone climbed off the Slayer's shoulder and seated itself on the table, looking up at the two. "Aw, hi little guy."

Meanwhile, Professor Kukui had skidded to a stop outside the lab. He burst through the doors and raced past the secretary and up the stairs. He skidded into the lab and paused when he saw his wife and the Doom Slayer looking over a diagram.

"Hey, hon!" She called with a wave. "You gotta meet this guy! This stuff is amazing!"

"Burn, that guy is some sort of warrior from hell. If you anger him, he could kill everyone in this room."

"Yeah, his A.I. buddy gave me the scoop. Apparently, he believed this place was going to open a portal to hell!"

"Okay, so he's didn't come here to threaten everyone? You guys are okay?"

"He saw something on the screen and he punched a monitor really hard." Burnet remarked, looking over to a smoking monitor, a giant fist-shaped hole in the center. "He won't say what angered him though."

About two hours passed, the group talked and VEGA shared information that would provide useful to them, and the Slayer was heading back towards the Tide Song hotel. As he left the lab, two figures stepped out in front of him. The Slayer also saw the group of kids from earlier, and they seemed to know what was happening. While Lillie seemed nervous, Ash clearly seemed to be thinking: 'Great. These two again.'

"Prepare for trouble!" A man declared.

"And make it double!" The woman added.

"To protect the world from devastation!"

"To unite all peoples within our nation!"

"Slayer, do you have any idea what is happening?" VEGA asked.

"To denounce the evils of truth and love!" They continued.

"To extend our reach to the stars above!"

"Jessie!"

"Jame-"

The Slayer walked through the two, clearly uninterested in whoever they were or whatever they wanted.

"…well, that was rude." James remarked, his eyes narrowed.

"The nerve of some people!" Jesse seethed in irritation. "Arbok! Poison gas!"

A largesnake pokémon suddenly slithered in front of the Doom Slayer and unleashed a sickening gas blast of toxic fumes. The Doom Slayer paused, and as the cloud dissipated, and the Slayer looked down in anger, covering Cubone's mouth. He looked to Lillie, and handed her the frightened Cubone. He looked at the snake, who was nervous as to what was about to happen to it, when he remembered what Tammy had told him.

"They follow orders."

The Doom Slayer turned around and looked at Jesse and James. The two members of Team Rocket looked in shock at the figure, and then pulled out his chainsaw. With one pull, he brought the weapon to life, roaring as the blade began spinning. He began walking back towards the two, dragging the chainsaw alongside him, the sparks flying as he reached behind him, pulling out his shotgun. Racking a slug with one hand, he stood about four feet away and simply stared at Jesse and James, as well as a weird Venus-fly trap like pokémon. VEGA began searching through his files for some sort of information on the group who tried threatening them. Finally, he settles on pulling up a clip from a movie the staff at UAC would watch.

"Your move, creep."

The two members of Team Rocket looked to one another, their plan of knocking the Doom Slayer out and taking his gear falling apart in front of them.

"…okay, this is not how I saw this day going." James confessed. However, the Slayer had stopped moving, making it clear that he was ready to go if that's what they wanted. Unfortunately, Jesse wasn't ready to give up.

"So, poison doesn't work? Fine!" She snapped. "Arbok! Use crunch!"

The Slayer turned around and simply looked at the Arbok. The pokémon seemed to be debating something, then shot forward and chomped down on the Slayer's forearm, trying to get it to let go of the shotgun. The Slayer felt what he believed were fangs lightly poking his skin, he was genuinely surprised that this pokémon had managed to penetrate his armour. The Slayer made a fist and brought it down on the Arbok's head. The snake hissed in pain and seemed to shrivel up, letting go of the Slayer's arm. The Slayer grabbed it and threw it to Jesse's feet, then decided he had enough of this. Without warning, he pulled his rocket launcher out and fired a rocket at Team Rocket. There was a sizable explosion, and Jesse, James, and their pokémon were sent flying.

"Looks like Team Rocket's blasting off againnnn…" They screamed as they flew, disappearing into the sky. The Slayer turned around, and put his rocket launcher away, then saw the beige cat from before. Although he saw it for the first time because he hadn't seen it earlier.

"Uhhh…" Meowth said, his eyes darting back and forth. "I 'a… Y'know… I've been meanin' ta take a vacation. Y'know, hit the beaches, get some Squirtle Slushy's… I'll just leave ya to whateva' you're all doin'."

The Slayer looked at the cat pokémon, then took a step back, motioning for Meowth to go right ahead with his vacation plans. The member of Team Rocket looked around and then ran off, not wanting to be near whoever this guy was.

"Are you alright?" Ash finally asked.

"Yes, the Slayer is fine." VEGA answered. "However, he is uncertain as to how that snake creature was able to break through his armour, but other than that, all is fine."

"Those three were Team Rocket." Ash explained, answering the unasked question. "They're members of a crime group, but those three aren't really good at their job. But they're kinda resilient, so I doubt you've seen the last of them."

"Oh, great." VEGA said, almost sounding sarcastic. Lillie looked down at the Cubone, who seemed to have calmed down, but coughed slightly.

"Oh, the poor thing…" Lillie said sadly, walking over to the Slayer. "I think he's been poisoned. We should get him to a Pokémon Center, they can help him."

The Slayer nodded, taking the Cubone from her and holding it close. He really seemed to care for it, and there seemed to be a mixture of regret, and anger emanating off from him. He looked to Lillie and she began to lead him towards the nearby Pokémon Center.

"Hey, is it just me… or does Lillie seem really confident around the Slayer?" Ash asked, watching them walk away. "Also, should we go with them?"

"Yes, to both of those questions." Hau nodded and the two ran to catch up with Lillie. Kukui watched as the two left, deep in thought.

"Hey, honey? Is everyone alright?" Burnet asked, looking at the smoking impact mark from where the explosion had happened.

"I think. Yeah." Kukui replied. "But something's coming. I don't know what, and I don't know how. But the Doom Slayer is a key part in all of it…"