Chapter 16

March 5, 2168

0925 Hours

Mjolnir.

What a strange name. Even more so considering that it was the name for a suit of armor rather than the mighty hammer it was based off of. However, considering that the Spartans were supposed to be living weapons in themselves, Izuku decided that particular detail could be overlooked. Besides, there was one feature above all others that the armor and mythological weapon had in common.

"Only the worthy may wield it," Izuku muttered under his breath. Those were the words that Doctor Halsey had said upon revealing the armor.

"A little grandiose, I know," Doctor Shield chuckled. "But she's not wrong. In order to wear this thing, you have to be physiologically beyond anything a normal human can achieve. Most strength quirks wouldn't be able to handle this suit. Honestly, I could probably count on one hand how many people I know who can wear this thing without breaking every bone in their body…well, there's probably more than that, but you get the idea."

"Is it really that dangerous? For me it just feels… natural. Like I was meant to wear it."

Another chuckle. "It takes a lot more than strength alone to use this thing. Halsey's told me a lot about your training and augmentations. The control you have over your own body is far above what the average person can manage. I'm honestly surprised that all of you have been able to adapt to it so easily. To you, it must seem more like a second skin than anything else."

Izuku agreed with a hum and went back to studying his armor. It was fascinating. He could feel the liquid nanocrystal in the bodysuit moving; shifting to conform to the shape of its occupant. It was the second strangest sensation he'd ever experienced. The first, undoubtedly went to the feeling he got whenever he moved - or rather, when the armor moved.

"Alright, now, slowly lift your arms up to your sides. Just like how we taught you," the Doctor ordered.

Izuku remembered their instructions. In his mind, he visualized the action of moving his arms. In response, the neural interface at the base of his skull detected these thoughts and sent the directions down to the suit. Without so much as twitching a muscle, Izuku's arms began to rise.

"Woah," he whispered.

This time, Doctor Shield erupted into full-on laughter. "The others had the same reaction."

After a few more hearty chuckles, he got to work. He went between inspecting the armor and typing things into the datapad he held. Once satisfied, he spoke up. "Ready to take your first step?"

"Of course," Izuku said with a smile. The Doctor shuffled out of his way and he put all of their instructions to the test.

Walking with the armor on proved to be… fluid; far more so than it had any right to be. With each step he only grew more confident.

"How much did you say this thing weighed, again?" Izuku asked.

"A little more than 450 kilos," Doctor Shield answered.

"Twice that of SPI," he realized. "Yet, I feel weightless."

He brought his hands up to his face and experimentally flexed them into fists a few times. "Weightless, but stronger."

Shield typed one more thing into his datapad. "Good. Now for the final piece."

Izuku walked over to the table and picked up his helmet. In his Mjolnir clad hands, the titanium alloy headwear was as light as a feather. He turned around and inspected the thing from front to back. Unlike the rest of their armor, each Spartan had received a different helmet. Some were - in Izuku's personal opinion - quite goofy looking, whereas others were simplistic, and a couple were downright menacing. His helmet was in the second category.

The Air Assault variant, with its sophisticated communications array and specialized optics suite would be an absolute boon for his style. The large, triangular visor was also a welcome feature. He'd have hated to be stuck with the narrow visors of Serin's Recon or Hitoshi's Commando helmets. He didn't see how they could be so comfortable with such a narrowed field of view.

Satisfied with what he saw, he slid it onto his head and heard the mechanisms lock into place. Data and programming filled his vision as the VISR software calibrated for its new user. The new VISR 4.0 operating system had been specially crafted for Mjolnir. With the benefit of their newly acquired neural interface, they could now use the system by simply thinking about it. No buttons or voice commands needed.

He turned to the Doctor. "How do I look?"

His eyes narrowed as he scrutinized the Spartan from head to toe. Then he gave a soft smile. "Like a hero."

"Thank you, Doctor," Izuku sincerely replied. It was good to hear that despite being under almost half a metric ton of titanium armor, he could still appear heroic. "I can't begin to imagine just how much you've helped us."

"You haven't seen the last of me," he sternly remarked. "Not by a long shot. Even when we'd put the finishing touches on these suits, Catherine and I couldn't help but consider everything else we could add. I've already got several ideas for the newest model. Once I'm back on I-Island, it's back to the fabricator for me!"

"A new model already? How many are there?"

"What you're wearing is the Mark IV. But with all the ideas that we've been bouncing off of each other, it'll be an entirely new beast."

"We're already on four? What happened to the other three?"

"Failed prototypes or models that simply didn't make the cut," he said with a wave of his hand. "They were either too bulky, didn't have a good enough power supply, or were too weak. The armor you're wearing - the Mark IV - is the first one to meet all our standards."

"Huh!" Izuku exclaimed. He was honestly astonished. They'd gone through four entire models until they finally designed one that met their expectations. How much time had that cost them? How many resources?

They really do only accept the best, Izuku thought.

"That's enough chit-chat for now. You're all set! Go on and meet with Doctor Halsey and the others in the testing area. I've still got several more Spartans to get suited up. Hey, and take it easy for a while, too! You still don't know just how strong you are."

"I will, Doctor. And thank you. For all of this."

"Not a problem. You lot are the future, you know that? It's only right that we do everything we can. Now get out of here and go test out your new gear!"

Izuku followed the signs to the testing chamber. Upon entering, he was greeted by a cacophony of sounds. Metal clashed, treadmills hummed, scientists talked while typing away on their datapads, and even the sound of gunfire could be heard from the indoor gun range. In the middle of it all stood Doctor Halsey herself.

She turned towards him. "There you are, Izuku. I hope Doctor Shield didn't bother you too much. He's always been exceptionally sociable."

Izuku grinned beneath his helmet. "Not at all, Doctor. We just talked about the armor and its functions. It really wasn't any different from talking with Mei, if I'm being honest."

She frowned and beckoned him over. Once close enough, she leaned in and whispered, "He didn't ask too many questions, did he?"

"Don't worry, Doctor. We only talked about the suit," he assured her.

She nodded her head with a sigh of relief. "Good. Very good. I…truth be told, I didn't need him here. My staff and I could've handled all of this. But I couldn't take the chance. No matter how unlikely the possibilities were, I couldn't risk something happening and him not being around. I won't lose anymore of you. Not if I can help it."

Izuku stood steadfast. He knew that the deaths of his fellow Spartans had shaken them all, but he hadn't contemplated just how much it'd impacted Halsey. "It's alright, Doctor. You did what you felt was right."

Although she didn't visibly react to his words, he had a feeling that it'd done its job and helped to ease her mind. "Thank you for understanding, Izuku."

"No worries, Doctor. So, where'd you need me?"

Back to business, Halsey once more adopted a professional stance. "There's an opening on one of the treadmills over in the corner. Go ahead and start there."

Izuku climbed onto the machine and followed the accompanying scientist's commands. They started off slow, going at a steady 45 kilometers per hour. He found that he could maintain this pace for hours without so much as getting winded. But in Mjolnir? That was nothing.

"How fast-" Izuku cut himself off as a message displayed at the bottom of his HUD.

65.8 KPH

"Oh," he said in surprise. He'd been told that the suit had an onboard computer linked to his neural interface, but it was only now that he understood what that meant. Any calculations he needed to run could now be done with a single thought.

"Did the armor catch you off guard, too?" The scientist asked.

"Yeah. It really is like something out of a comic book." He might've said it like a joke, but in his mind he couldn't help but internally gawk at what the Doctors had created. What else did they have in store for the future?

"There's been a lot of comments like that lately. You're almost done here, just need to get a record of your maximum speed. You can go whenever you're ready, the machine is set to match your pace."

"Are you sure? Spartans are able to accelerate pretty fast."

"Unless you can outmatch someone like O'Clock or those other speedsters, then you'll have nothing to worry about."

"Well, in that case, here goes nothing!" His feet hammered against the machine with each step, resonating through the air like rolling thunder, adding to the symphony of chaos amongst others. In three quick strides, he went from around 65 kph to…

119.1 KPH

That.

He kept it up for a few minutes until he could feel his legs beginning to burn from the exertion. He gradually descended back into an easy 45 kph for another couple of minutes. Once done, he hopped off the treadmill and made his way towards the gun range. In an enclosed area separated from the rest of the laboratory, Izuku realized that it wasn't the Spartan who was doing the shooting. No. They were doing the exact opposite.

"Are you guys sure that the surgery didn't mess up my brain in any way?"

There was a round of laughter from the area from the scientists watching next to him. They stood safely behind two dozen centimeters of bulletproof glass, observing the Spartan who was currently being shot at by robots. One of the scientists finally explained the situation after their initial guffaw. "This isn't a figment of your imagination, this is reality. We set this test up not long after we discovered your 'Spartan Time' ability. With our calculations, we theorized that all of you had the speed and reflexes to pull this off."

"So we can dodge bullets, now?"

This day is just one surprise after the next, Izuku thought. I can't wait until Mei finds out about all this. She's probably gonna start drooling.

"Ready to step inside?" One of them asked.

"Did you even have to ask?" He countered.

Once they'd deactivated the robots, Izuku was able to swap places with the other Spartan - Mawata.

"You're having fun," she stated. She couldn't see his face, nor have heard him through the thick walls or the sounds of the gunfire, and her Quirk had nothing to do with being an empath. But she knew. She always did.

"Are you?" He asked.

She looked at the turrets, at the bullets that'd obviously missed their mark, and down towards her own set of armor. Then she faced him again and gave a small shrug.

He gave a short laugh in response. They held out their arms and knocked them against each other's armored gauntlets before parting ways. When the door closed, the speakers came to life.

"The exercise begins in five…four…three…two…"

The pair of turrets came to life and immediately trained their barrels on him. His breathing remained even and controlled as he tensed his body in anticipation.

"One."

Their muzzles flashed in a staccato beat as a flood of pistol caliber rounds tore through the air at supersonic speeds right towards his chest. He didn't have to worry if he'd failed. The titanium alloy plates of his Mjolnir would stop anything they shot at him. Even the weakest parts of his armor wouldn't be so much as scratched if the bullets connected.

But where was the fun in that?

He twisted his torso and the rounds sailed past him and impacted the titanium wall harmlessly. As the guns snapped to follow their target, Izuku lowered his center of gravity by crouching to the ground. He waited until the turrets corrected themselves and were fixed on him again. As they unleashed another wave of projectiles, he sprang from his position and leaped towards his side.

The turrets rounded on him, all the while still firing. His body was a blur as he engaged in this dance between man and machine. The bullets passed all around him. They whizzed past his head, flew between his legs, and whipped uselessly through the air around his chest and arms. Not once did he come close to being struck. That's when a thought formed in his head.

What does it feel like to get shot in this thing?

With his mind made up, he froze and allowed several of the rounds to hit their mark. The only reasons he could tell was because of the sharp ting sound they made when they stuck and his suit subsequently warning him that he was taking fire. Though it did clarify that he wasn't taking any damage.

He resumed his evasive maneuvers for another minute or two until the scientists announced that he had to move on to the next station. As he found himself back in the main room, the newest Spartan to receive their armor practically sauntered in.

"This is, without a doubt, the best thing ever invented," Mei declared. It was hard to tell her apart from all the other jet-black armored figures walking around the area. The only visible difference between them was their helmets, with hers being the "Operator" variant.

"You have no idea…" Izuku remarked.

"Nah, I'm pretty sure I do," she said with a shrug. "Doctor Shield and I got into a lot of the specifics of Mjolnir. Between the hydrostatic gel layer and the reactive liquid crystal, you could take a dive off of a skyscraper and still be fine. Probably tear one down, too. Did the calculations myself. With the suit's help, of course."

"What?" He gasped. The Doctor had told him that they'd be able to pull off some incredible feats, but this was starting to become insane.

"I wasn't joking - I'm telling you that this is the greatest thing ever created."

Izuku once more studied his armor, though it was with equal parts admiration and bewilderment. After everything he'd heard and witnessed, he came to one simple conclusion: this was no costume.

It wasn't meant to be a visual expression of their personalities or dazzle the public with intricate color schemes and fancy pieces. Hell, this wasn't even remotely similar to other exoskeletons like his SPI armor.

It was on a whole new level of its own.

XXXXX

Like the hunter she used to be, Tsutsumi-sensei stalked through the laboratory. She observed the Spartans from a distance, never coming close enough to warrant their attention. If Izuku had to guess, he'd say that she was sizing them up. Evaluating them for a mission.

Odd, but not unusual. After all, it was her that'd made the final decision on who would be assigned to the Assault Group during Operation: Nightcrawler. She'd done the exact same thing while the Spartans had been recovering from their augmentations. She'd scoped them out from the sidelines, seeing how they'd been adapting to their bodies and the loss of their comrades.

If the same thing was happening again - if she was here to assess them while they got used to their armor, then that meant there was another big operation in the works.

After fifteen minutes, it'd seemed that she'd come to a decision. She silently made her way towards Chimera's team leader - Serin - and said something. Then she went to Legacy's leader - Keiichi. Finally, she came to him. "Izuku, gather your teammates and follow me."

"Yes, ma'am," he dutifully replied. He went around the room, collected his friends, and hurried off after her. They walked in silence for several minutes until they entered a large briefing room.

Tsutsumi-sensei fired up the holo-projector and faced them. "Spartans: I've selected you for this mission because of your unique skill-sets and your history. This…"

She pointed to the first slew of images that formed. They detailed a large compound that looked like a combination between office buildings and a mansion. Large, imposing walls surrounded the area, but the pictures had been taken from a vantage point so they could easily see past them.

"...is the headquarters of the Yakuza group known as the Shie Hassaikai. The images you see here are courtesy of Fireteam Chimera's investigation. Through their efforts, we've been able to learn a great deal of information regarding the layout of their base, their command structure, size of their forces, and their arsenal."

Izuku was aware of the Shie Hassaikai. The Commission had been keeping a close eye on them with an ever-increasing amount of interest. As a result, so had the Spartans. Tsutsumi-sensei went through the important details: the layout of the compound, enemy resistance, and High Value Targets (HVTs). Then she threw something completely unexpected at them.

"Mythic Team: the things you've accomplished are impressive, don't get me wrong. But there was, ultimately, another reason why I selected you for this mission: your experience working alongside other Pro Heroes."

Realization dawned among the Spartans. "Ma'am?" Keiichi asked. "Are you saying-"

"That's right, Fireteams. This will be a joint operation between us, the police, and a number of Pro Hero agencies."

"Sounds like we're really going all out," said Will.

"And for good reason," she sighed. "This particular group of Yakuza have proven to be far more dangerous than any others in the past. Not to mention that the local agencies and law enforcement already have been running their own investigations into the group. Because of this, the Board's come to a decision: this operation will mark the debut of the Spartans."

This is it, Izuku thought. We're finally revealing ourselves to the world. And with quite the show, too.

"It won't be as in depth as other Pro Hero debuts, though we'll get into the specifics at the end of this briefing. Speaking of which, you'll have another briefing here in a week that will include the Pros and the police. It'll be of far less significance than what we'll be going over today. In fact, the things we'll be discussing are not, under any circumstances, to be shared with the other groups."

Izuku shared a look with Hitoshi. This was proving to be a very interesting day.

"In light of new information discovered after we decided to work alongside them, you'll find that you have… conflicting objectives."

Author's Note: This is gonna be a long one.

This chapter is supposed to serve as a brief introduction into what you should expect from Mjolnir since there will be some differences. Basically, it's the Mark IV just with a five-times strength enhancer instead of a double. Right now, the only difference between them is the helmets. As for the rest of the armor, they have the same set-up: jet black armor color with gold visor color. But those will change after a while, especially when they receive newer models.

You'll find that Spartans here are a little more capable than their canon counterparts. Spartans are supposed to be superior to a normal human in every way. Thing is, humans in MHA - even quirkless people - are shown to be quite a bit heartier than in real life. One person in particular is Endeavor.

Correct me if I'm wrong, but the dude's Quirk is only his fire and doesn't affect his physical abilities in any way. Yet he's been able to stop a charging Nomu and a speeding truck with his bare hands, without breaking a sweat. So yeah, since Spartans are supposed to be better in every physical way to non-strength enhanced humans, they're going to have a lot more vigor than in their own universe. Which is gonna be interesting because Spartans are already known to do some crazy stuff in Halo. And I mean crazy stuff. I'm talking some honest to god superhero level stuff.

Side Note: I accidentally referred to Serin's old team as Legacy in a previous chapter, which wasn't correct. Her old team's name was Justice. I've already gone back and edited that.