Synopsis: This is a bit of an interesting one, but hear me out. As bad as it may be, the concept of the DOOM games, especially the 2016 reboot and DOOM: Eternal has caused me to have a very strong desire to write a story featuring Doom Guy, or as he's more properly referred to now, Doom Slayer. So, here's what my crazy mind came up with. I hope you enjoy the story. *Side Note* I do not follow the main story for the games, I'm only building off of the simple plot presented, with some tweaks on names of monsters and stuff for sake of brevity. Despite how broken regular DOOM Slayer would be (he does some RIDICULOUS things within the lore and if given one for all, could probably make Goku pee his pants when his music kicks on), I will be trying to make it a little bit balanced, so that it isn't just Deku Slayer destroying everyone in his path. His challenges and problems will be different, but they will be there. So don't freak out on me if Izuku doesn't somehow beat all his problems. You'll see what I mean as we go on with the story. Anyway, onto the first chapter.

Chapter One: Going Home

He could see it trying to run. The small imp was one of the last remaining demons in this area, and it was scared of him. They all were. He didn't blame them. His younger self would've been scared of him too. He raised a double-barrelled shotgun at the running creature and clicked the second trigger on it. A small chain flew from below the barrels of the weapon and pierced the stomach of the imp. Just as quickly as it was shot out, it pulled him to the small creature, allowing him to fire the gun at point-blank range. The demon was easily blown to pieces, Blood and flesh flying in multiple directions.

With a practiced, fluid motion, he reloaded his shotgun. It'd been a very long time since he came here. He honestly should be dead. Ignoring the small, terrified person he was when he first came to the home of all evil, humans generally didn't live longer than 300 years. And yet, here he was, while physically larger in muscle and more developed, he had barely aged at all. A year at max. Time here was a finicky thing.

"Slayer, are you alive?" A voice echoed inside his helmet. Taking a breath, he put his hand up to his ear and pressed a small button. His voice was hoarse from lack of use.

"Yes."

"Good to hear? Any survivors?"

"No. They were killed and eaten before I got here."

There was silence on the other end. He knew that meant she was taking a moment to grieve for those poor soldiers. "Alright. The disturbance they were investigating should be just ahead."

"They should have waited for me." He said. There was silence on the other end for a long moment before she responded.

"Yes. They should have."

"Sorry."

"It's okay. You're getting used to people again. I was aware of that when we started."

"Hmm…" He put down his 'super shotgun' and pulled out his assault rifle as he walked down the hallway towards the disturbance. It was a simple task to continue taking down the multitude of imps and zombies that came barreling down the hallway. As he walked, gunning down the demons, he jumped over one that got too close, and slammed its head into the ground, splattering it all across the ground. He spun, kicking the head off another one before putting the assault rifle on his back and grabbing his shotgun. Shell after shell flew out of the gun, tearing apart all the demons nearby.

As the last one fell to the ground, he shook his head. "This is too easy. Is everything else dead?"

"You already killed the King of Demons just two days ago and the Dragon yesterday. It'll be a long time before anything so dangerous spawns."

"Hm…"

"Yeah. You're right. It feels like a trap. But there's nothing on the radar, so for now, you're okay."

"I wasn't worried about me."

"I know." He laughed at that comment, kicking one of the dead zombies before moving to the large, wooden doors. He didn't wait long before kicking them wide open. Inside the room, the floors and walls seemed to be almost flesh-like. Blood and veins ran around the entirety of the room, leading towards a large pedestal in the middle of the room. In the middle of the pedestal sat a large, pulsating red gem.

"Well… That's different." He said softly, not letting his guard drop for an instant.

"Yeah. That seems important. Why is it here, though?"

"Second question. Where's it's Guardian?" He said, looking around the room. As if on cue, he heard the sound of a clack from above him. He dashed forward, barely moving away in time to avoid being crushed by a large, Blood red monster. It seemed to be an amalgamation of creatures as if all the creatures he normally fought had been combined to make a terrifying, new demon.

"Well. That's certainly a Guardian."

"Hm." He readied his shotgun at the large monstrosity. "This shouldn't take long. Let me know when you're done figuring out what that thing is."

"Will do. Be careful Slayer."

He didn't respond. They both knew what the answer to that was. The beast charged him, but with how telegraphed its movements were, it was a simple task to avoid it, firing a couple of rounds into its legs. The Monster turned rather quickly and unleashed a flurry of bullets, rockets, and other projectiles at him, but they were easily avoided or brushed off for the most part. His Slayer armor kept him from harm.

The creature began trying to crush him as he ran around it, releasing shot after shot into its knees. It didn't seem to like the treatment as it pounded its foot into the ground, sending him flying backward. It was easy to recover from, however, so he was quickly able to dodge the follow-up missiles that came with it. The fist, on the other hand, was not dodged and sent him careening into the wall.

"Slayer!"

"I'm fine." He sighed as he stood up from the rubble, the monster charging after him. "The Dragon and the Icon of Sin were far more dangerous than this thing."

As the creature went to hit him again, he jumped over the hit and used his super shotgun to pierce its shoulder with a chain and pull him over to it. It attempted to shake him off, but he dug one hand underneath right at the shoulder rockets and fired the chain into the ground. With the awkward grip he had, he pulled the creature to the ground, as well as easily separating the weapon from its shoulder. As it tried to stand up, it froze as he stood at its neck, the Hell blade extended.

"You have been one of the most disappointing creatures I have yet to fight." He said, grinning underneath his helmet. "Good. That means your kind isn't much of a threat anymore."

He didn't give it time to move before he cut its mouth off. It writhed in pain and began to scramble to stand, only for him to jump to its one eyes and grab it with one hand. It came out easily with a loud pop. More blood gushed and it was shaking and attacking itself desperately to get him off of it. Still holding on tightly, he pulled out the largest weapon in his arsenal, a large, glowing green weapon, and jammed it into the socket. He said nothing as the weapon revved up briefly before unleashing the devastating, destructive energy into its eye. The plasma ripped its body to pieces, forcing him to have to jump back to avoid getting hurt by it too. He watched the bloody carnage happen for nearly a minute till nothing remained of the large monster.

"Easy."

"Yeah. That was rather anticlimactic. But it is the first chapter. We'll just have to give it some time."

"Hm?"

"Nothing." He heard typing on the other end before she said anything else. "Aha, got it. I figured out what it is. Wait… Woah… are you serious?"

"What is it?"

"Slayer… that's the demon gem. The only thing keeping this place together after you killed the Dragon and the King."

He looked at the gem in surprise. It looked so fragile, almost like it was nothing but a cool treasure to find in 6th edition Dungeons and Dragons adventure. Yet, here it stood. The one thing that had caused so much misery, death, and pain over the last three hundred years.

"Are you sure?"

"Positive."

"Then you know what I have to do. "

"Yes."

"Do you have any objections?"

"No. We both knew this would be a possibility if we found it. And there's no reason to wait until we have a guaranteed way out. It's better for the rest of humanity if we do it now."

"Agreed." He walked slowly over to the gem, crushing the eye he'd pulled out earlier underneath his boot as he did so. The flesh surrounding the pedestal squished and sagged underneath him, but held his weight. When he reached the gem, he could hear the sounds of energy or blood flowing from the gem into the veins on the pedestal. He gripped the gemstone in his hands. It felt alive, similar to many of the hearts of other demons he'd killed, and he could feel the evil intent rippling off of it. Yet, it felt hardened, almost pathetic.

"Slayer?"

"Yeah?"

"Before you do that, can I ask you one thing?"

"Sure."

"What's your real name?"

He smiled. It felt oddly appropriate that he should be asked that question in possibly his final moments. It had been so long since he said his name or even remembered where he'd been before coming here. He might as well go out with one person in this corrupted place knowing who he was.

"Izuku. Izuku Midoriya."

There was silence on the other side of the line for a few moments before Izuku heard a small intake of breath.

"It's nice to finally meet you, Izuku. I'm Melissa Shield. I'll see you on the other side."

"Alright, Melissa. You're buying drinks." Izuku chuckled. It'd been something he did with all the other soldiers he'd ever fought with. It only felt right to say it here.

"Fair enough. I'll see you there."

Izuku didn't wait another moment. He pressed down hard on the gem, crushing it in his grip. There was a loud shriek and a rush of air and liquid as it broke in his grasp. Everything began to fall in around him, the room and reality itself closed in around him. The loud sounds of metal screeching, flesh being mangled, and the dead screaming echoed in his ears. And then, nothing. Hell ceased to exist. And so did he.

…

Or so he thought. It took his brain a moment to catch up with what his eyes were seeing. He was sitting in a small bedroom, from the looks of it. The walls were blue… A color he hadn't seen much of in a long time. Books littered his desk and pictures of a large, muscular man with blond hair covered the walls. It felt familiar, yet it was hard to place it. Where was he? He was positive he wasn't dead, so this had to be something else. Or rather, somewhere else. But where?

"Izuku!" Izuku froze at hearing a voice he'd almost long forgotten. But no matter how long it'd been, he knew who it was. "Izuku, are you almost ready to go? The exam for UA starts soon!"

UA? He hadn't heard that name since he'd gone to Hell. Had he… Had he returned home? Was he back home? And right when he'd disappeared as well? What was going on?

"Izuku? Are you okay?" Izuku could hear his mom approaching his room. It took a moment for Izuku to think of a solution. He wasn't used to interaction, nor was this a good situation to be caught in. For some forsaken reason, he was still in his Slayer armor. Quickly taking off his helmet, he cleared his throat before speaking.

"Yeah, mom, I'm fine. Give me a bit, I'm almost done changing." The footsteps stopped just outside the door.

"Okay, dear. But hurry, we don't want you to be late."

"Understood." He didn't question why she didn't ask him about his voice being a bit deeper. He was a year older. Well, three hundred years older, but no one would know except him. He looked at his armor. He didn't feel comfortable taking it off, and he couldn't see anywhere he could hide it. But on the flip side, it would be really hard to explain how he'd gotten the armor, for now. It would be impossible to play it off as a gift from… All Might if he remembered right, at least till after he got into UA. Izuku looked over his room once more. Maybe he could find some room in the closet. But this might take a while.

…

Izuku sighed as he walked towards the entrance to the UA entrance exam. It was nowhere near easy to act as if no time had passed. His conversation with his mother showed him he had forgotten a lot of things. Thankfully, his mother didn't seem to notice it. He would have to figure out what was going on later. Right now, he was focused on living the dream he'd had all those years ago, now that he had a chance again. As well as the strength to do so. But the dream felt hollow after so long, and confusing. For now, he'd have to just go with the flow.

He turned a corner and looked at the large gates leading to the auditorium they'd been directed to meet in. The campus was huge, almost as big as the Slayer's Corps barracks. He stood still for a moment to take it in. This felt so surreal. For years after his arrival in Hell, he'd only dreamed of coming back. He'd given up on that dream for so long, it felt so weird to be back in a place where it was a possibility.

"Move it, extra." Izuku felt someone bump into him but barely moved. He looked over questioningly to see who it was to see an explosive haired blond glaring him down. The blond went to say something more before stopping, staring at him in shock.

"Deku?" It took Izuku a long moment to respond to the person in front of him. And he knew that name was some name meant for him. He knew he should know, he did. But because of how long it'd been, his mind wasn't cooperating. So he took the safe route.

"Yeah?"

"What the [*censored*] happened to you?" The teen grinned maliciously. The grin was enough for some old memories to click and a name came to mind.

"Training, Bakugo."

"Pft. As if that'll be enough for your quirkless self." Bakugo laughed, before shoving Izuku. The combined weight of his armor and his natural strength caused him to not move, though the explosive teen didn't notice. Izuku watched silently as Bakugo left, walking towards the place where most of the examinees were gathering. Izuku shook his head, holding back a smile. It was hard to take Bakugou seriously when he had literally stepped on things scarier than the angsty teen.

"Hey, are you okay?" Izuku turned to see someone he knew he didn't recognize approaching him. A young girl with brown hair and pink circles on her cheeks was walking towards him. "That guy seemed pretty mean."

"Hm. That's just how he is."

"Oh! Do you know him?" He knew his answer should be yes. He technically did' know' him. Or at least he should. But he did not have enough memories of the apparent 'bully' to actually, sincerely mean it.

"Vaguely," Izuku said, letting out a small sigh, and shaking his head.

"Oh. Well, I'm glad you're doing alright. My name's Ochako Uraraka, nice to meet you!"

"I see." Izuku nodded, looking the girl over briefly. It was hard not to think of her as someone younger than him. Everyone seemed like a child compared to what he was used to. Yet, he was 'technically' fifteen years old. Or sixteen, rather. "I'm Izuku Midoriya."

"Okay. Well, I'll be going then. Nice to meet you, Midoriya!" Uraraka said before running off, waving. Izuku waved for a brief moment before shaking his head. He needed to get used to interacting with people again, and that very stiff conversation was the perfect example.

Deciding to wait for later, Izuku pressed forward into the place where the students were gathering. It didn't take long to find his assigned seat. Which was right next to Bakugou. Great.

Bakugou thankfully didn't do much more than letting out an annoyed sound and roll his eyes. Izuku sat down and waited the few minutes it took before finally someone stepped out and walked towards the center of the stage.

(Authors Note: Yes, this is not the same as the anime. The idea is there, however. Don't flame me).

"Gooooooooooooood morning, examinees! It's nice to see you here. Can I get some energy here with a HEY?!"

Dead silence. No one said a single thing. Izuku raised an eyebrow at the high energy guy on the stage. Who was this guy? He needed to read through all those journals he had on his desk again. His memory was not helping him remember all the fanboy information he had had previously.

Unfazed, the excited blond with speakers around his neck continued. "Alright! Well, today we're gonna be holding the practical exam to enter UA! The way the test works will be pretty simple." A screen behind the presenter kicked on to show a picture of four silhouettes. They seemed to be robots of some form, from what Izuku could tell.

"For this exam, you listeners will all break off to take the practical exam at different mock city locations. In the exam, you'll have ten minutes to navigate the city and earn points. There are three robot 'villains' you can defeat to earn points. There are one-pointer, two-pointer, and three-pointer villains, with the ones with more points being more difficult. Your goal is to have as many points as you can before the end of the exam."

Izuku nodded. The objective was simple, and right up his alley. It seemed this test was the perfect fit for him. Next to him, Bakugou scoffed as he looked at their ID cards for which mock city they would be heading to.

"Tsk. Looks like they don't want you working together with people you know." Taking a glance down at their cards, Izuku saw what he meant, with Bakugou being in exam sight A and himself in exam sight B.

"It appears so."

"Dang it. Now I can't beat your sorry [*censor*] into the ground."

"Of course, you can't fight other listeners, because that would be unheroic." Izuku smiled at that sentence. In the middle of his explanation, the man paused as someone shouted from in front of Izuku.

"May I ask a question?"

"Sure"

"Sir!" A tall, dark blue-haired student that was rather tall stood up quickly. "On the handout that was given to us it shows that there are four kinds of robots that we will be encountering, yet there are said to only be three. If this is a misprint, then UA, a prestigious school in Japan, should be ashamed of this foolish mistake."

The student turned around and pointed directly at Izuku.

"Well, examinee 7111, to the first thing, you are correct. There is a fourth robot that is worth no points, which is why I didn't mention it earlier. It's pretty tough and meant more as an obstacle rather than something you should fight. If you encounter, I'd say you listeners should run as fast as you can!"

"I see." The blue-haired student said, bowing in apology. "I am sorry for the outburst."

"No problem examine 7111. Any other questions? No? Then LETS. GET. STARTED! Off to your mock battle stations. Good luck suffering, listeners!"

…

Different busses labeled for the different mock test sites were waiting outside and dropped the students off at their assigned locations. Izuku stood amongst the students, waiting at the front of the entrance to the exam site for the test to begin. As he looked over the large group of people, there were very many interesting characters there. Some seemed like other creatures, with wings, tails, horns, all sorts of different colors, and appendages. It was odd to look at the vast assortment and realize they were all 100% human, not demons. Yet, Izuku gladly welcomed the change. He needed it.

While he was looking over the group of students, he noticed the girl he had met earlier. Ochako? Wait, Japan. Last names. Uraraka. He'd been around so many Americans, his own culture felt slightly foreign to him. He went to go walk over to her when he felt a hand on his shoulder.

"And just what do you think you're doing?" Izuku looked over his shoulder to see the blue-haired kid behind him. Izuku wasn't sure whether he should ignore him or respond. But brushing the guy off didn't feel right, nor did responding angrily.

"Is there a problem with me talking to her?"

"She, like the rest of us, is here to take the exam. No matter how pure your intentions, it does not give you the right to distract her from the exam."

Izuku raised his eyebrow again. This time, he turned completely to face him as some nearby people whispered rather nervously.

"What's your name?" The other teen stiffened slightly at the question before adjusting his glasses to look Izuku squarely in the eyes. While the teen was taller than Izuku, Izuku was, how to put it, 'larger in stature.'

"Tenya Ilda, a graduate of Somei academy."

"Hm. Well Te-, Scuse me, Ilda. I am not aiming to disadvantage others. I am simply looking to do my best to be a hero. That means using everything I can to pass. I am not aiming to distract Uraraka but engage in conversation. Is it not normal for people to talk to each other?"

"Er. Well, yes, but-"

"Then what is wrong with me talking to her?"

Before either of them could say anything more, the loud voice of the earlier present echoed from speakers as the gates opened.

"Start!"

Izuku needed no further prompting and was off like a rocket. He dashed into the city. He ran as fast as he could to where he could hear the sounds of metal moving. Turning a corner, he spotted two large robots with missiles on them labeled 2. Their red sensors focused on him, and they aimed their weapons at him. And that's as far as they got before Izuku rushed forward and grabbed their heads and crushed them into the ground, shattering them to pieces. Izuku smiled as he looked up to see more robots, one pointer, turning the corner.

"Well, a Slayer never tires…"

…

"Woah! We got a good group of students!" The blond teacher laughed, looking over the cameras to the different block sites.

"Indeed, Present Mic." a rather attractive woman in a skin-tight bodysuit said, laughing. "We have quite the year ahead of us."

"Yes, this year's batch will be quite interesting." a large, concrete man added, his blockhead nodding with his words.

"You're being too optimistic." The two looked at a man with long, black hair and red eyes. His eyes were sunken as if he were tired. "Most of these kids don't look any different than every other year we've had."

"That may be true, Aizawa," A small, bear-rodent man said, smiling at him, "But I can feel something different in the energy they have."

"Hm. We'll see Principal Nezu." Aizawa shook his head. "Speaking of, All Might isn't your student in one of these groups."

All Might jumped slightly, tearing his gaze away from the cameras. "Huh? Why, yes of course. Mi- my student is in this group of applicants."

"Well. We'll see how good he is." Aizawa muttered before turning back to the cameras. All Might felt a bead of sweat run down his head. He wanted to respond, but he turned back to the cameras and looked at the one following his student with worry. Izuku Mirodoriya.

'Izuku.' The number one hero looked at the camera showing Izuku with worry. Izuku was bigger than he remembered him being and fighting with skill and brutality that he could guarantee he did not teach him. Something wasn't right, here. But he'd have to stay silent for now.

"Well, I think it's about time to start the fun part of the exam." Principal Nezu grinned, before motioning to Present Mic. The Radio Hero grinned before pressing the large red button on the console.

…

Izuku felt pretty good so far. He'd been tearing through the robot's pretty easily. Even without his guns, these things were less dangerous to him than imps or zombies. It was a walk in the park to tear them apart. He was sure he had more than enough points to pass and was starting to head towards the main group of students. He might as well get a look at who his new classmates might be.

It was then there was a large explosion and the ground beneath him began to shake. Izuku turned to where he'd felt the shaking start and looked for the source. Many of the students that were running or fighting in the main streets did so as well. A shadow fell across the street as a Giant robot, taller than all the buildings looked down on them.

'The Zero-Pointer, huh?' Izuku shifted his stance, readying himself to run or move at the first signs of danger. 'That seems a bit extreme for a bunch of kids trying to become students.

A lot of people stared in shock while Izuku began to move to a nearby alleyway. As expected, the robot pulled back and punched the ground faster than most of the students could react. Wind and dust shot down the street. Izuku avoided most of it, but the ground still shook.

Izuku watched as many of the students began to run away from the zero-pointer. As they ran, Izuku could hear the sound of the announcer dude saying they had two minutes left. Izuku didn't need more points as he already had nearly seventy-something points, but it would be entertaining. He turned back down the alleyway and started to run.

"Ow."

Izuku stopped on a dime. He turned around immediately and looked to see who was hurt. There, with her leg buried underneath a large piece of debris just outside her reach, was Uraraka. And the treads of the Giant Zero-pointer were approaching her quickly.

Acting on instinct, Izuku ran at full speed towards the girl. She looked up to him in worry and fear. She was panicking. It only took him a second to reach the trapped teen before he grabbed the debris and lifted it off of Uraraka. He knelt next to her, Uraraka looking up nervously at him.

"How's your leg?" Izuku asked.

"It hurts a lot," Uraraka said, holding her leg in pain. Izuku looked back to the robot. It was too close for him to be able to pick up Uraraka and run.

"D'arvit." Izuku chuckled at the word, but his features hardened as the Robot pulled back his hand. Izuku knew what it was going to do.

'Dang it. There is no way I could get Uraraka out of here with her hurt. What do I do?' Izuku's muscles tensed and watched as its arm began to move towards him. 'I am not letting this end here!'

Izuku felt a weird sensation begin to course through his body. An unnatural strength even more than he was used to from the Berserker strength he had accessed in his time during Hell rushed through his body. In his mind, he felt words echo in his mind. Words he hadn't heard since before he went to Hell.

'Clench your butt and scream these words from the bottom of your heart!'

"Smash!" Izuku threw his fist directly into the arm of the robot. Power rippled through his arm and the robot's arm blew to pieces. Electricity shot across Izuku's body. Not waiting for the robot to recover, he jumped high into the air. When he didn't quite reach its head, he pushed down hard, using the small bit of demon energy he'd learned to jump off the Air. The robot adjusted the course of its hand to try and attack Izuku who now stood in front of its head.

"You made a mistake," Izuku grinned, grabbing the robot's other arm before it made contact with him. "You never attack that while a Slayer is still breathing."

The strength in his body was beyond anything he'd ever experienced and everything he'd done to every demon he'd faced felt like child's play with how easily ripped off the robot's arm. He leaped off the robot, wielding the robot's arm as a weapon before once again jumping off the air to spin and use the arm as a club and slam its head. As the robot's head crumpled, explosions rippled down its body, and it fell limp where it was, falling away from the panicking students. Izuku had defeated the 0-pointer.

…

Everyone in the judging area watched the cameras for area B in shock. The power and efficiency shown here were far beyond what they had expected. Most students who attempted to fight the 0-pointer would be gunning to get inside it. However, this student had defeated the robot in a contest of physical strength. With relative ease, if how he acted was anything to go by.

"Oh. Oh My." Principal Nezu said, calmly taking a drink of his tea. "That was quite the feat."

"Well well, what do you know. We have a really interesting group. That boy is special." the woman said, smiling eerily.

"Indeed." The cement man agreed. "That boy has a bright future ahead of him."

"Hm. He's strong, I'll give him that. And he knows how to use his head." Aizawa muttered. All Might said nothing, as he was smiling at the camera showing Izuku.

'There it is.' He thought. 'There's that heroic desire and passion that made me choose you to be my successor.' All Might chuckled, but then frowned. 'But what happened to you Izuku? What changed you?'