A few minutes prior.

Oscar's shield blocked most of Aiden's deadly strikes, leaving a few clean, burned cuts on the outlines of his body. For the briefest of moments, he swerved his body, adjusted the position of his limbs, and minimized his exposed areas to dodge the excess of the slashes. But Aiden's swords were unrelenting, and his best efforts still amounted to numerous cuts and burns scattered around his figure. At least the damage was minimal. He had the means to keep fighting.

'Show me. Show me more.' Oscar carefully observed, glimpsing into Aiden's movements, not a single hair escaping his gaze. From the Counter Impact, he knew the secret to the powerful spells was hidden in Reis and Eirin. Escaping certain death thanks to Demon's interference, Oscar backed away, an intense stare directed at the wondrous flames.

When it came to Reis, it always ended up in steps. Adamasreis, Omnireus, and others all started from one step to the next until completion. Oscar wondered as he danced around the battlefield, sidestepping the flame apparitions, their fast blades brushing past the ends of his hair, scorching them slightly. He kicked one, driving a Golden Lance into its chest, and rebounded to the second, a single bash from his shield reducing it into a dying ember. Quickly, he fired a Golden Breaker and tore a hole into the head of the third.

His gaze never left Aiden. The Prinstyct observed and relayed the movement of Ein before it obscured into Eirin. Sevon once mentioned and lamented having no chance to learn the secret techniques of Reis and Eirin meant for only the core members of the Volten blood. Even though he was to marry into the family, he had no right due to his blood. In all of the battles against the New Dawn, Oscar never witnessed the powerful mastery of Eirin and spells Aiden showed.

Blood splurted from the fresh cuts, sizzling into a blackened char as they barely traveled down his skin. Flames rode through the gaps in the cuts like rivers between shores and seared them up. Yet, his head remained surprisingly clear. Beyond the pain of his flesh burning and sharp blades slicing his tendons, clarity let him see truly, and excitement numbed the worst. How long had it been? How long since he last delved into the depths of Reis? Adam and Sevon taught him well, but not much beyond what he already knew.

This was new. All the questions and curious inquires were brushed aside, his mind honing on only to observe the enemy. 'What did you see?' His master's favorite phrase echoed in his ears. Indeed, what did he see? Oscar smiled, unable to contain his excitement, even during the strife and horror on the surface right now. He mulled on that single question, and it seemed Aiden had enough, a flicker of emotion shaking that stoic expression.

As Aiden shouted out, unnerved by his actions, Oscar provoked further to stir his foe's Ein, a more distinct picture drawing in the Prinstyct world of distortion. Back to back with Demon, he endured the rain of deadly arcs of flame, darting his sight over every infernal blade. A sudden understanding dawned on him. Reis came in steps. In Adamasreis, it was step by step to reach full completion, then the Pseudoguise, then the Guise.

The steps for Aiden's strange power entered the spotlight in his mind.

The first step was Reis enhancing spells externally, a simple coating over the already formed spell. The second step was to invoke spells using Eirin, resulting in a spell many times more powerful than the norm. Aiden's power must be the third and perhaps final step. Oscar tugged on Demon's arm, pulling his alter ego out of a killing blow, and likewise, Demon pushed them away from another.

'That's the trick. Interesting. I was the first to discover the Eirin for us, so I'll leave this to you.' Demon stopped Aiden's sword in its place and countered, only to be saved by Oscar's quick kick, Aiden unable to fully counter any of them. Still, the wounds piled on. Oscar held in the groan of pain rising from his tired lungs, the heavy, hot air not helping to ease the suffering.

'Feel it.' Oscar felt time slow as each cut formed on his body. Learning through the pain and feeling of the blow was the way ingrained in him by his master. The Eirin inside the flaming slashes that cut into his body held the secret. And the Ein's movements before they merged into Eirin ignited the spark. His body paid the price, but his life clung to his mind as it unraveled the mystery.

Aiden's Ein started as tendrils…no, lines would be the more appropriate. These lines of Ein, already divided, fused with Reis, but the concentrated weight that sliced the surface of his shield expressed only a single line. His wounds gave the final piece to the puzzle—the feeling of countless lines coiled and condensed into a singular line embedded into his very skin.

"I see…so it's like this?" Oscar dragged his weary body away and formed a Golden Drill, his artificial arm clenching tightly within the metal. His seared lungs drew in a deep breath, and his Ein, divided into the thinnest lines, fused with his Reis into Eirin, and the Eirin moved akin to strings weaved into a loom, the end of his drill. Some of the Eirin transformed into fine lines of fire. He gritted his teeth against the immense rejection of countless lines of Eirin and fire fighting and repelling every other line. They refused to become a single line.

'Weave.' At long last, the line responded to his will. They coiled and combined, a single line becoming infinitely smaller down to a point on the tip of his drill. Oscar thrust forward, his Shattering Wave not erupting in a wild blow that filled half the chamber but firing in a single path, a line. Widened eyes greeted his blow as Aiden crossed his swords and canceled the Shattering Wave.

'It's not there yet.' Oscar stared at his hands and raised his voice against Aiden's, bringing his arm up, eager to witness the fruits of his pained efforts. Lines of Ein turned to lines of Eirin that further transformed into lines of metal and fire. The concentration and limit of his capacity solved the mystery of why Aiden created fewer of these blades. The sheer weight of containing the power and the mental drain of control were taxing.

The lines devoured each other until a few remained, six in total, and they invoked the combination of Blazing Blades and Golden Rods. Scarlet swords floated around him, golden edges gleaming brightly as the magma glowed from underneath. Drenched in cold sweat, Oscar glanced at Aiden, who smiled widely for the first time during their battle.

"Come on!" Aiden shouted, raising his red blades.

Oscar did not disappoint him and sent the six scarlet-gold swords out, the sharp metal whistling across as the flames roared in the burning trails of their path. Aiden swung his blades faster than ever and cut each of Oscar's swords cleanly in half. For a final touch, he sent forth another cross slash, containing so much Eirin that the Guise flickered out momentarily. The chamber trembled, and the magma lake swayed.

Oscar stomped forward. His Golden Drill combined flawlessly with another fire spell, completely different from before. Sparkles of gold flashed across the dense ruby-like surface of the drill. He created the fine line for a concentrated Omnireus, the air distorting from the emanations of his Eirin. He willed his strength, targeting the cross slash, and met the blow head-on. The magma lake churned, tides of flames ending the once peaceful surface.

His body was knocked back, and so was Aiden. The lake caved in the center, a crater deepening into the depths. Oscar smiled. The drill was still cut slightly from the tip. But it withstood Aiden's sword to near perfection. Oscar chuckled and reformed the drill back to normal. He spoke calmly, "Thank you for teaching me the next step."

Aiden's brow twitched, and a moment of silence fell between the two, then he broke out in heavy laughter, his arms still ready to defend. "Sirsi was right. You discovered one of the secret Reis techniques simply by observing me. Your talent for Reis is unbelievable. No wonder she's so desperate to be on your good side. If it were the old times before Kaen, the Voltens would have welcomed you with all the fine luxuries."

"Perhaps I would have accepted the offer of the old Voltens, but not any of you. By the way, what is this technique called?" Oscar asked.

"It's not a technique. It's been known as the final concept of Vis, a principle of a true Reis user." Aiden said. He suddenly veered left and blocked Demon's surprise attack. Smiling wider, he dodged Demon's kick and retreated further away. "More surprises! You reformed the double with the final concept. I admit it. You are now a worthy opponent."

His surprise attack had failed. The so-called final concept worked wonders for his Duality, pure lines of Eirin merging into a single brilliant line that formed the body. Demon's power surpassed the limits of Duality, which should only have been limited to half his strength. Oscar recalled Demon to retreat to his side since the other battle was nearly settled.

A faint neigh, gargled by blood, filled the quiet chamber, and Borinn tumbled over, stopping when Aiden caught him. Severe punctures into the Equsimus' stalwart flesh, bled sizzling blood, half of the face being caved in by a brutal blow. Aiden lifted up his steed and grimaced at the arrival of Erden, who fared better than his mythical rival. But the shattered plating around the sapphire armor and a broken antler wing were not the injuries to brush off.

"Are you ok, Erden?" Oscar called out.

"Never felt better. But you're worse than I thought." Erden brushed his nose against Oscar's wounds and licked off some charred scabs. The three of them, Oscar, Erden, and Demon, glared at Aiden, who tended to Borinn. The final concept of Eirin boosted his strength, but Aiden's power could not be measured.

Aiden rose and patted Borinn's head with a slight smile. "We're done here."

Stunned, Oscar blurted out, "Done? Do you believe we are finished here? After the destruction you've wrought?"

"Oh, how insignificant your worries are for what is insignificant. My duty is now finished." A font of Ein poured out from the hole in the magma lake, incredibly dense and horrifying. Oscar could not believe something so powerful could rest below his home. Aiden entered the rising pillar of Ein and relaxed, a peaceful expression resting on the warrior's face. "It is done. Thank you, Oscar, for living up to your reputation."

"What have you done?" Oscar charged toward the font, but even a powerful, concentrated Omnireus failed to break through the dense barrier around it.

"What we should have done thousands of years ago." Aiden stretched out his hand. "I am Aiden Volten. The blood in my veins calls you home."