Combining Sacred Gears. Kanata knew it was possible to have one Sacred Gear affect another, or even to truly fuse them. That was why he believed he could combine the power of his own Sacred Gear with Lavinia's.
Fusing Sacred Gears and incorporating their power. It reminded him of the Dividing Gear, which Issei Hyoudou had created by combining the power of the White Dragon Emperor with that of the Red Dragon Emperor. Using it came at a great cost, shortening his lifespan, but a large part of that was likely due to combining two opposing Sacred Gears.
There were other examples, like Genshirou Saji's Vritra Promotion, which combined the Vritra-type Sacred Gears. Kanata reasoned that as long as the Sacred Gears were compatible and the hosts had a strong enough will, their powers could be used without repelling each other. His gamble, born from that conviction, paid off magnificently.
The Ice Princess, pierced by the crimson Sacred Gear, was now wreathed in the light of deletion it had absorbed. Kanata's and Lavinia's Sacred Gears had been so compatible from the start that they had even caused a resonance phenomenon. The two artifacts merged without any rejection, complementing each other's powers.
And so, with the birth of the azure Longinus harboring a crimson core, the dream match of Robot versus Dragon began—at least, in their minds.
"Alright, here we come, Tannin! Delete Inertia! Delete Air Resistance! Delete Impact!"
"Tch—!"
Kanata issued the command from his original Sacred Gear, manipulating the abilities of the spear he had deconstructed and fused, which now held three slots of his deletion power. In response, the Demise Gear Doll emitted a strong crimson light from its entire body and floated silently into the air. The wings on its back adjusted to maintain balance. Then, the Ice Princess kicked off the air and charged toward the colossal figure before it with blinding speed.
Tannin reacted with a speed unimaginable for his size, dodging at the last second. The shadow of the charging figure shot past him and crashed violently into the rock wall behind. A deafening roar echoed through the area, leaving a large, crater-like hole. A three-meter mass was ramming into things at high speed without any concern for damage. Even for a dragon, it was not something to be taken lightly. The sheer force of the impact erased any trace of carelessness from Tannin's eyes.
The Demise Gear Doll emerged from the hole, half of its face shattered and the section from its shoulder down completely destroyed. But ice immediately swirled around it, restoring it to its original form. This Sacred Gear would not stop unless Lavinia was defeated or her mental energy ran out. The Ice Princess, now empowered by Kanata's Sacred Gear, was a perfect fusion.
One of the characteristics of ice is its weight. As a solid mass, it possessed physical attack power, but that same mass made it a Sacred Gear that lacked mobility. Its immense weight prevented it from achieving high speeds. For that reason, Absolute Demise itself was not suited for close combat; it was an Independent Avatar-type Sacred Gear that focused on defense through its hardness and regeneration, as well as special attacks using ice. That fundamental premise had just been shattered.
The weight that hindered its speed was gone, yet the mass and hardness that served as its weapons remained. Furthermore, its regenerative ability allowed it to deliver high-speed blows repeatedly without worrying about damage. On top of that, the effect of Absolute Demise was still active, meaning any part of an opponent it touched would be frozen. In other words, Tannin had to dodge every single high-speed, high-mass attack.
"Lavinia, are you okay?"
"Y-Yes. But this is quite the handful to control…"
"The area of effect is huge, so it's taking a lot out of me, too. So, just as we planned."
"A short, decisive battle," she finished.
This was a combination technique they were trying for the first time. Lavinia was struggling with the new method of controlling her Sacred Gear, and Kanata was expending a great deal of energy to affect such a massive Longinus. They had already determined that a prolonged fight was impossible. The two of them nodded to each other and focused their consciousness on their respective Sacred Gears. Red and blue auras enveloped the Ice Princess as it closed in on Tannin with movements even more agile than before.
"Hmph, interesting!"
Tannin's lips curled into an amused grin as he flapped his wings and leaped into the air, taking the fight to the sky. The doll's four arms moved independently, trying to slash at him as he spun and dodged with nimble movements. He countered its special ice attacks with his fire breath, neutralizing them.
He tried to overwhelm it with a blast of flame, but its speed made it impossible to catch. In a straight line, it was likely even faster than Tannin for a brief moment. Furthermore, his own fifteen-meter frame made him a large target, and he nearly took a hit from the smaller, faster opponent several times.
The rule of this battle was that Tannin would lose if he took a single hit. He could block the attacks, but if he was struck, the additional freezing effect would activate, sealing his defeat. The moment the small ice doll touched him, the fight would be over. Realizing that close combat was disadvantageous, he chose to create distance.
He would defeat it with long-range fire or demonic energy. He reasoned that they wouldn't be able to utilize their strengths from a distance.
"Long-range battle, Lavinia."
"Yes, it is time to show my Sacred Gear's true potential."
Sweat beaded on her forehead as Lavinia nodded forcefully. Then, a "whirring" sound and a glowing light, as if something was being charged, emanated from the Demise Gear Doll. Even Tannin paused at the unusual activity, while Azazel's eyes lit up as he clenched his fists.
"Is it that?! Of course, when you think of a robot's long-range attack, it has to be that!"
"What is 'that,' Azazel?!"
"Dreams, passion, and romance!"
"I don't understand!"
Perhaps I should reconsider my association with this man, Tannin thought.
"It is ready."
"I'm good to go, too. Alright, on three!"
"ROCKET MISSILE, FIRE!" they both shouted.
The blue and red auras concentrated on a single point of the Demise Gear Doll at their command. And then, an ice missile wreathed in high-density aura shot straight toward Tannin. From its chest.
"A missile just flew out of its chest?!"
"You two, why wasn't that a rocket punch?! What am I supposed to do with all this excitement I had built up?!" Azazel yelled.
"But, Professor, the Demise Gear Doll is a female model. It's common sense for it to shoot missiles—made of ice—from its chest."
"Tch—?! T-To think that I, in my excitement, could have forgotten such a basic fact. Dammit, to be taught a lesson by my own student… The path of a teacher is deep…!"
"You loud-mouthed bystander of a Fallen Angel Governor! Shut up for a minute!"
Tannin dodged the continuous barrage of breast missiles wrapped in the deletion effect, dealing with them without a scratch. However, his spirit seemed to have already taken a direct hit.
"Enough of these cheap tricks!"
Tired of the missiles and even more tired of the commentary, Tannin spread his wings and flew through the storm of projectiles at top speed, soaring above the Demise Gear Doll. Having taken the high ground, the Blaze Meteor Dragon opened its mouth wide and unleashed a massive stream of fire at the ice princess. Even a Longinus would be instantly vaporized by such a flame.
"Lavinia, purge!"
"Demise Gear Doll!"
At Lavinia's command, the doll used its own hands to pull out the ice shard with the spear embedded in it, transforming it into a smaller doll. It then hurled this smaller form out of the flame's effective range with all its might. Aided by the reduction in mass and the effect of the Sacred Gear, the small ice doll moved at high speed, escaping the fire and—vanishing.
"It disappeared?"
He had successfully incinerated the large ice princess, but as he turned his gaze to pursue the part that had escaped, Tannin blinked at the strange phenomenon. For a moment, he wondered if it had burned up from the high-speed throw, but he trusted the faint aura he sensed and the alarm bells ringing in his mind and immediately fled from his position. An instant later, a blast of icy breath rained down on the spot where he had just been. He looked up to see the fully repaired Demise Gear Doll, now hovering majestically above him.
"I see, you erased its presence and appearance."
He had seen Kanata's Sacred Gear abilities over the past two weeks. The boy had gotten much better at concealing his aura. Thus, he could understand the phenomenon, but if this had been his first time seeing it, he might have taken a hit. The thought brought a small, irrepressible laugh to his lips.
He had started this training with the intention of lending his chest as a former Dragon King. But look at him now. The thrill of battle, the anticipation of what they would show him next. He truly could not predict what they would pull off.
If Tannin stopped holding back, this fight would be over in an instant. But that would be boring. He wanted to see more of the potential these two children were showing him. He was curious to see what they would accomplish as they continued to grow.
"I see, this is indeed interesting."
The Sacred Gear was strong, but they were beings who did not drown in that strength, who sought to understand it and struggled to grow alongside it. He didn't know how they would develop, and it would likely take time, but he was sure they would never be boring to watch. He had a lifespan that was mind-bogglingly long. It wouldn't be so bad to watch over them as one of his personal amusements.
Kanata and Lavinia were likely unaware that they were achieving results in this battle that far exceeded his expectations. However, the Dragon King was not so soft as to let them win. Their stamina and mental energy had to be running out soon. As a reward for entertaining him, he decided to teach them one more lesson, a ferocious smile spreading across his face.
"Well done, Kanata Kuramoto. And you, Lavinia. …But, if I were the enemy, this is how I would strike."
The Sacred Gear Unison they had devised was certainly powerful. However, at its core, it was still an Independent Avatar-type Sacred Gear based on the Absolute Demise. This meant that the Sacred Gear's fundamental weakness remained. No matter how strong the artifact, it was all over if the host was defeated.
Tannin instantly kneaded his demonic energy, imbuing it with the power of fire. He threw it at the Demise Gear Doll, binding the opponent, whose reaction was a fraction too late. The heat of the flame and the power of the ice clashed, creating a thick white mist. The doll seemed to be using its ice and deletion powers to try and break free from the demonic energy, but it would buy him a few seconds. And a few seconds were all Tannin needed.
Lavinia would be fully occupied controlling her Sacred Gear. And Kanata was already using three of his slots for the Sacred Gear Unison, meaning he couldn't use his deletion effect for anything else at the moment. The last slot he had left was being used to survive in the Underworld. Therefore, he absolutely could not turn it off. In other words, they were currently defenseless.
Consider this a lesson. Tannin launched a fireball at Kanata and Lavinia below, at a speed he calculated Azazel could intercept. The two of them widened their eyes at the sudden flame hurtling toward them, but—there was no panic. They exchanged a look and nodded.
"Now, Lavinia!"
As Kanata shouted, Lavinia took a step forward and threw her arms around him. Ignoring Azazel, who let out a whistle, Kanata activated his Sacred Gear's ability. He was manipulating air resistance. For just a momentary movement, just long enough to escape the flame's range, his body would hold. He changed his final deletion slot, his face contorting from the backlash, but he held Lavinia tight and escaped the fireball's range with all his might.
Tannin's eyes widened. That last deletion slot was one of Kanata's lifelines. The Underworld was toxic to a mere human in many ways. The effect that deleted the harmful influences of the air and soil was a line that should never be crossed. And yet, he had crossed it without hesitation. Even if it was just for a moment, he could have died if he was unlucky. Tannin had thought Azazel would step in to stop such a reckless move, but he didn't move. On the contrary, he was smiling.
"So that's it. He wasn't using his last deletion effect to adapt to the Underworld in the first place. That's why he's been sticking so close to Lavinia."
"What?"
As Azazel spoke, Tannin looked at Kanata and saw a pale blue film of light shimmering around him. That was the aura of Lavinia's Sacred Gear. Furthermore, he was enveloped in the presence of magic. He must have had Lavinia cast a spell on him beforehand to allow him to adapt to the Underworld. With the magic and the aura of Lavinia's Longinus, Kanata could survive in the Underworld for a few minutes. And he had been using his last power slot to hide it.
What Kanata had been deleting all along was the wave of the special effects emanating from himself. By doing so, he had concealed the fact that he was clad in the aura of magic and Lavinia's Sacred Gear. Along with his final trump card.
"Now, Demise Gear Doll!" Lavinia shouted urgently while still being held by Kanata.
Her command drew Tannin's attention back to the Sacred Gear. As if in response to her voice, the ice princess, which had been struggling against the fire magic, stopped moving and suddenly shattered into countless pieces.
In this battle, Tannin would lose if he took a single hit. Therefore, rather than dodging the countless ice shards of all sizes raining down from above, Tannin chose certainty. He instantly incinerated them with his fire breath, completely erasing the ice that was falling from the sky.
It was a close call, but Kanata's deconstructed Sacred Gear had also vanished with the ice in the flames. Lavinia likely had no power left to create the Longinus again. Other than their combination technique, they had no other way to land a blow on Tannin. The battle was decided. Having weathered their final attack, Tannin slowly stopped his fire breath.
—And at the same moment, he felt a fleeting, searing pain from his foot.
"Tch—!"
It was pure reflex. An instinctive rejection and a chill. He kicked the object that had hit the sole of his foot with his claws. The object collided with the ground with a small sound and broke.
"...So, the special effect you truly wanted to hide from me wasn't the magic or Lavinia's Sacred Gear's aura, but this one's."
If he had sensed this aura from Kanata during the battle, he would have been on high alert from the start. That was why Kanata had kept it hidden with his Sacred Gear, so Tannin wouldn't notice. The magic and Sacred Gear auras were just another layer of concealment to hide his true trump card. They had gone to such lengths to hide it. Because this was something that couldn't be overcome with power. It was an instinctive, characteristic, and the greatest weakness of a devil.
Lying there was the bent, final spear Kanata had been holding. The spear alone shouldn't have caused any pain. But tied to its tip was a silver ornament. It had shattered to pieces on impact, but he instantly understood what it was.
"Honestly, we knew it would be difficult to land a hit on you in a head-on power struggle, even with the Sacred Gear Unison. You're strong, Tannin, and your skin is tough. You're an amazing dragon. But you're a formerdragon. You're a reincarnated devil, which means you're weak to light and holy objects."
The Sacred Gear Unison wasn't their only trump card. That was why they were able to react immediately when Tannin attacked them. And they had turned it into a perfect opportunity to create an opening. Kanata erased the shattered spear and picked up the broken silver ornament. It did nothing when a human touched it. But for a devil, it was a different story.
"The cross you brought for the Underworld?"
"Yes. Honestly, I just brought it as a good luck charm, but I never thought it would be useful like this."
As Kanata laughed, scratching his head, Azazel shrugged his shoulders in exasperation. For these two, the Sacred Gear Unison technique had been a decoy; their real plan had been to figure out how to hit Tannin with this cross all along. They had used the weakness of the Independent Avatar-type Sacred Gear to their advantage to create an opening, continuously erased the holy aura of the cross so he wouldn't notice, and at a moment of carelessness, threw the spear to hit the reincarnated devil dragon's foot with the cross. For a devil, mere contact was enough to cause an effect.
It was certainly a single hit, but it was a hit meant only for this one purpose. It would be meaningless in a real battle. In fact, Tannin only felt a slight pain and was perfectly fine. But in the context of this training, it was a hit of great significance.
"Professor, Professor. You said any single blow was fine, right? You never said we had to land a blow with our own power," Kanata said cheekily.
"Ah, well, that's true."
"Rest assured, I have no intention of contesting the outcome. But still… you cunning little brat."
"Hey, ow-ow-ow! Tannin, you're crushing me! If you grind your giant finger into my head like that, my head's gonna pop off!"
Even after landing a blow on a highest-class devil dragon, the boy was the same as ever. He had come up with the Sacred Gear Unison and the cross trick on a whim, so he probably didn't fully realize what an incredible thing he had just done.
Lavinia let out a sigh of relief and sat down on the ground. It was no wonder, after having to control that Longinus for so long. It was hard to tell if she, either, truly understood what she had just accomplished. Tannin's defeat was due to him underestimating their power. It wasn't pure power, but the unseen force of potential that had delivered that one blow.
"As a reward for defeating me, I will train you further the next time you come to the Underworld. You'd best be prepared."
"Eh… Wait, that's not a reward! That's just a punishment!"
"Oh, that's great, Kanata! A highest-class devil and one of the most powerful beings in the Underworld is going to train you personally. What an amazing reward! Do your best not to die."
That's just too cruel! Don't abandon me, Azazel! Kanata pleaded tearfully against the terror of the dragon, but the adults simply ignored him, as if a breeze had blown by.
"There, there, Kana."
"That goes for you too," Tannin said mercilessly to Lavinia, who had been comforting Kanata.
"...Oh, dear."
After that, the children, their eyes spinning from the exhaustion of the battle and the content of their "reward," fell asleep on the spot as if they had fainted. It was unlikely they would wake up anytime soon. Since they couldn't return like this, they ended up spending another night in the Underworld.
Azazel contacted Mephisto about it, and when he explained the details, Mephisto was exasperated in more ways than one. However, he apparently made a doting-parent comment, saying, "A red and blue combination Sacred Gear sounds just like me." Afterward, Azazel and Tannin were both scolded for bullying the children too much. It goes without saying that when Kanata and Lavinia heard about this later, their fondness for Mephisto grew even stronger.
Their job in the Underworld was successfully completed, and they had even discovered new possibilities in their training. And so, their days spent with the dragons in the Underworld.
***
10 Advanced Chapters Available on my Patreon!
https://patreon.com/Well_being