After finishing breakfast, Andrew, Sindy, and Nathan arrived at the training room with the aid of their new phones.

Upon arriving, they noticed it was filled with many dome-shaped structures that seemed to be used for training purposes. The domes had glass ceilings and white metallic walls that were aesthetically pleasing to the eyes.

"So these are the newbie assassins Alondo told me about..!" Suddenly exclaimed a cool deep voice from behind. "...The girl looks like an annoying brat, the blonde kid looks dumb, and that last one is a twig..."

The friends then turned around to see a tall muscular man around his early thirties. He wore dark sunglasses with a huge cigarette perched against his lips. He had a slightly shaved beard, black spiky hair with faded sides, an army-green jacket with camouflage pants, and big leather boots.

"Uh— who are you..?" Asked Sindy curiously.

Instead of responding, the man rudely placed his massive hand on top of Nathan's head before he began squeezing it like a rubber ball.

"Hmm... So, you're the Mind Hero... You're tinier than I expected. You have a lack of muscle build-up and you look poor in any form of physical activity..! Is Alondo sure he got the right person?"

"Ouch! You're hurting me!" Squealed Nathan in pain.

"Sorry kid, you just seem pretty pathetic is all."

"Who is this monster?" Trembled Andrew.

"I don't know, but he better not try anything dumb," threatened Sindy.

The man then paused before taking a puff of his huge cigarette, rudely releasing smoke in Sindy's face.

"Ahh alright! Let me introduce myself to you newbies. My name is Brady. I'll be your teacher and team leader. You can call me Instructor Brady, or Senpai Brady, or maybe just Senpai..! Whichever you like but I personally like Senpai!"

"This gorilla is gonna be our teacher?!" Squealed Andrew.

Instructor Brady then quickly draped Andrew by his shirt, "Who are you calling a gorilla, pipsqueak?! Call me that again and I'll kill you!"

Andrew quickly nodded in submission before allowing the instructor to release him.

"Hahaha! Now then, let me welcome you three to AA! As of today, I'll be responsible for you. I'll train you, take you on missions, feed you, and put you to sleep! You got that?"

"Yes sir!" The three replied submissively.

Instructor Brady continued, "Okay, so let me see if I got your names right... It's Mindy, Andre, and Note, right?"

"No, I'm Sindy! Sindy Williams..."

"Yeah and I'm not Andre... It's Andrew... Andrew Blake..."

"And I'm not Note... I'm Nathan, Nathan Styles..."

"Alright, whatever! I'm not good with names but follow me. It's time to train!"

The three were then led inside one of the dome-like structures they had seen earlier. It was much bigger than it had seemed from the outside.

"Okay, so this is what we call a leisure dome. It's a dome designed specifically for training assassins to their limits. It works by converting your body into Spirit Energy which is then transferred inside the dome in a physical form. Due to this, any injuries, pain, or deaths that have been received while inside of the dome are reversed once you exit."

The three friends were impressed. They liked the idea of being able to train without any limitations that even nullified the chances of death. This would help them become much more capable in battle over just a short period.

"The training will be harder than anything you've faced in your pathetic lives so far. Are you all ready?"

"Not a problem! I'm prepared to do whatever it takes to become strong enough to save everyone... I'm going to become the greatest hero this world has ever known!" Exclaimed Nathan with a flaming look in his eyes.

"Also, Instructor," began Sindy, "You mentioned something about Spirit Energy. I take it that's the energy people in the Mind World use to cast these so-called Arts?"

"Wow, Mindy! You're smart for a blonde!"

"Thanks, I guess? And it's Sindy..."

"Can we begin training already? I wanna kick some ass with my new superpowers!" Rejoiced, Andrew.

It was evident that Sindy and Andrew held just as much determination as Nathan. They were surprisingly enjoying themselves. They had expected a very harsh world but it seemed like it would be pretty easy. Little did they know, this chain of thought would soon be their downfall.

"Okay, I like your spunk kids, so let's get started. Over here we got an aura detector. Simply place your hand on the screen and let your spiritual energy flow through."

"I know Sindy already gave us a hint about what Spirit Energy is but do you mind going a little more in-depth?" Queried Nathan.

"Yes, Spiritual Energy, or SE for short, is the energy that allows us to wield powers known as Arts. Each of us are born with at least two specific types of SE or Art styles if you rather. The type of SE you have will determine your position in battle."

The Instructor then paused to puff his cigar before continuing, "Spiritual Energy is divided into three main classes that we humans name the Art styles. These include; The Natural Arts, The Light Arts, and The Dark Arts.

These Arts are further sub-divided into a variety of sub-arts but there are way too many of them to list. There are so many in fact, that no one even knows them all."

"Okay, fair enough. But in terms of ranking, which Arts are the strongest?" Asked Nathan.

"The Dark and Light Arts are the most powerful but they're quite rare. Most people end up with only the Natural Arts. However, Arts alone do not determine one's strength, kids. Hard work and dedication can beat talent any day!"

"Alright, I'm feeling this! So how do I channel my Spiritual Energy into the Aura Detector?" Asked Andrew as he ran towards the machine.

The instructor sighed, "Just place your hand on the Aura Detector and visualize yourself pumping energy into it. A tingly feeling will develop if you're doing it correctly."

"Alright, guys! Watch me walk out with a Rasengan or a Kamehameha!"

Andrew then walked over to the aura detector and placed his hand on its scanner. He then started channeling his Spirit Energy into the machine. Shortly after, his hand became tingly and hot as if it was soaking in hot water. The machine then buzzed notifying that the scan was complete.

Andrew was a Dark/Natural Art user. His Arts were that of the Destruction Art from the Dark Art category and Water Art from the Natural Arts. His Destructive Art was his main capability.

"Bro! This is hype! I got a rare and overpowered Art!" Boasted Andrew.

"Hmph, not bad kid," Complimented the Instructor. "Destruction Art is quite powerful but it's considered to be one of the more dangerous Dark Arts. Be careful with how you use it."

"Yes, Senpai!"

"Mindy, you're up next!"

Sindy approached the detector cautiously. She didn't know what to expect from the strange machine, "Okay, and it's Sindy!"

The scan then began as Sindy felt the same tingling that Andrew had felt before. Her Art Styles soon came to be revealed as that of the Light/Natural Arts. She had the ability of the Regeneration Art from the Light Arts category and Fire Art from that of the Natural Arts. The Regeneration Art was her main capability.

"So another rare... But it seems you're more of a healer type even though you got massive firepower to back you up. Well done, Mindy!"

"Sindy!!"

Knowing it was his turn, Nathan nervously approached the detector. He needed a powerful Art to be able to protect the people he cared about. He then took a deep breath and placed his hand on the detector. This was when something unexpected happened.

Instead of simply pinpointing his Arts as the detector had done with Sindy and Andrew, it immediately detected Triple Art User.

"Woah!!!" Shouted Instructor Brady in shock.

"W-what is it?!" Panicked Nathan.

"Nathan, you're a Triple Art User! Very few people are lucky enough to be born with three types of Spiritual Energy within them..! If a Triple Art User manages to master all three of their Arts, they usually become much more powerful than a regular Double Art user. I guess you aren't the Mind Hero for no reason..."

"So what do we do now..?" Asked Nathan cautiously.

"Continue the scan! I need to see something..!"

Nathan then did as the Instructor told him and continued the scan. His Art styles derived from the Dark and Natural Arts. He was capable of the Death Art which derived from the Dark Arts. He also had Lightning and Wind Arts which both derived from the Natural Arts. His main Art was however that of the Death Art.

The instructor's eyes widened with distress as he could hardly believe what he had seen.

"Ridiculous! I know you're the Mind Hero but a Triple Art User?! There is only one other person in this entire organization who can wield three Arts!"

"So Nathan's godly compared to everyone else?" Asked Andrew sarcastically.

Instructor Brady then slowly puffed his cigar as if to ease some stress, "Well, it depends on how you look at it. From my perspective, it's more of a curse than a blessing. Spirit Energy should be able to flow in equilibrium within one's body. The addition of a third Art disrupts that flow completely. The energy is spread randomly inside that person rather than becoming equalized like a regular Double Art user.

Simply, the energies inside you will fight for dominance. To make it worse, you wield the Death Art, Nathan. The Death Art is one of the more powerful Dark Arts. I'd say it's ranked #2 under the Catastrophic Art. An Art like that is already hard enough to control as it is. Even a simple Double Art user would struggle to keep it under control. Its nature is just that aggressive."

The images of what had happened between the wolf-like creature and Nathan flooded Sindy's mind. Just the power of that dark energy added to a piece of wood was enough to send that giant creature hurling through five trees. Not to mention that Nathan's hand was injured by the force.

"So what's he going to have to do then..?" Asked Sindy worriedly.

"Hard to say, but he will have to come up with his own method for channeling that Art to keep it in equilibrium. As for now, I rebuke you from using that Art, Nathan. You shall not try to activate it, you shall not speak of it, nor shall you even think about it. As it stands, you're nothing more than a walking time bomb waiting to go off. You're a danger to us all. Practice only your Lightning and Wind Arts to perfection."

"Wait, I know you said that it was more a curse than a blessing but is it really that bad..?" Murmured Nathan.

"No more questions about it! Rely on that power only if you intend to hurt those around you!"

The Instructor's words echoed through Nathan's head. The last thing he would want was to hurt any of his friends. He agreed he would not activate his Death Art no matter the situation.

However, the real truth was that Instructor Brady had picked up on something within his Death Art. Death Art was truly a powerful Art but he would never tell someone not to use it under normal circumstances. Nathan's Death Art seemed abnormal and extremely sinister. He however wasn't about to bring the topic up. He didn't want to scare them.

"Okay, I won't lie. I like you kids. You're all gifted and contain enormous amounts of potential. Nathan, don't worry too much about your Death Art. I'm sure someday you'll be able to use it freely without hesitation. Until that day comes, work hard to achieve it."

"Yes sir! I'll do my best! I promise!"

"I'd rather you call me Senpai, but sure. I won't take it easy on any of you. You will train twelve hours a day for an entire month. Your training begins now!"

The days then passed by slowly. Every day, the Instructor placed them under extreme physical training to increase muscle build-up and stamina. He taught them how to fight and defend themselves with and without weapons— in case of numerous situations.

Somedays, he made them do friendly spars with one another, while other days he fought them himself. Their speed, quick thinking, and teamwork became second nature. He taught them different ways to make use of their Arts and how to create unique moves from them. He made them endure different kinds of pain and counted every drop of sweat that fell from their bodies.

At the end of it all, the friends were much stronger and smarter than before. Their first real mission approached and they had no intention of failing it.