Acnologia stood stoic in his human form before Kai, his arm crossed, a wicked sneer spread across his face. Kai maintained a hardened expression. Nerves rattled his insides but he also kept up a solid stance. Acnologia's tremendous magical pressure did want to make his knees buckle.
Erza and Wendy remained behind him for one moment longer before Erza called for Wendy.
"Let's go. We need to cover a lot of ground."
"Do come back, girl," Acnologia said, his eyes falling on Wendy. "I'll make you next. Maybe I'll save the most appetizing meal for last."
"I said you won't harm her."
"I don't care about what you have to say, boy."
"You won't touch my mother."
Acnologia laughed. "Mother? Perhaps I should kill you too, then, if you are a dragon-sire."
Kai twisted his blade, the glint of it catching in Acnologia's eye and forcing his attention back on Kai.
"I'll make an exception for this meal," Acnologia said. "I wanted to save you for last, Kai, to savor your death and make you beg for my sister in the end. Perhaps I'll get the chance to do that when your little friends return hoping to see you triumphant."
"Get going," Kai said, turning a bit toward Erza and Wendy. "We don't have all day."
"I love you," Erza said, suddenly, as Wendy rushed back into the house.
Kai smiled back at her. "I'll see you soon."
Erza jogged back into the house with Wendy, even Requipping into a new armor set. They fled out the back way, Kai sensing how far they were before letting out a great sigh of relief, leaving he and Acnologia alone.
Acnologia's cape rippled in the gust of wind sweeping the countryside away from the nearby sea. He gestured at the sword in Kai's hand.
"You hope that weapon will be able to harm me? There are no such weapons."
"And you have no words that'll stop me from trying," Kai said.
Acnologia retained his hubristic expression and exerted even more pressure against Kai, who remained unflinching.
"Believe it or not, in my seclusion, I have kept up with your goings-on. I had to know what sort of life my sister's child led. To my surprise it is quite a tainted one. Uncontrollable magic. A lust for a woman who for years could not return it. Knowing you are always second fiddle to other, stronger wizards. And the best one yet? Seeking the help of Hades to become strong enough to slay me, as if that would've ever even helped and staved off your imminent destruction!"
"If that's all you know then clearly you haven't been paying attention."
"You have sinned, Kai, on your path to being the hero hat slays the mighty Apocalypse Dragon."
"I wouldn't a hero if I didn't sin. Heroes are born from goodness, they're born from a desire to do better. And I have."
"Not good enough."
Acnologia raised his lone arm and fired a pulse of magic at Kai faster than any spell Kai had ever seen. Still, Kai held his stance and deflected the magic back with his own sword, careening the force into the side of the cliff where it shattered.
"Oh," Acnologia muttered, nodding. "Good."
"I won't lose to you," Kai said. "It's over, Acnologia."
Acnologia said nothing but fired off a stronger pulse of magic that Kai had to dodge. Kai swiped his sword through the air, a clean slice of magic ripping across the sky before Acnologia swatted it away effortlessly. Acnologia curled a fist and two reams of blue magic burst from the ground beneath Kai before the entire ground before Kai exploded and sank away.
Kai shot away from it, having used a shield to block it that shattered quite easily.
Acnologia took advantage of the moment and launched at Kai, punching at him.
Kai slammed his feet in the ground and returned the attack, catching Acnologia's fist much to the dragon's utter surprise.
"Maybe magic won't work on you!" Kai roared. "But I can still beat the hell out of you with my own two fists!"
Acnologia glared at Kai who tried to knee Acnologia but was blocked, and instead Kai used the opening to punch Acnologia hard across the face, sending him stumbling back. Acnologia sneered at Kai, who spun around and kicked Acnologia away. The dragon slid back from Kai.
"I won't call it luck," Acnologia grumbled. "I'll call it oversight on my end. I managed to take that fool God Serena by surprise and the Dragon Queen anticipated me."
"Maybe you should expect more of s's son."
Acnologia spat at the sound of his sister's name. "You truly do believe it your destiny to slay me, don't you?"
"Maybe once I did, but no longer. My destiny now is to protect my guild and my family. If I can do that? I'll die happy."
"If that is the case then I'll make sure to destroy your guild before you die. I'll string you on every step of the way, making you watch as I burn it all to the ground."
A searing heat roared in Kai's chest, and his magical aura burst around him. Acnologia gestured for Kai to attack once more. And maybe, long ago, he would've. But this time he hung back.
"Oh, how mature," Acnologia growled. He straightened up. "Kairi would be so proud."
"She's proud of me enough for getting this far," Kai said. "She's proud of me for standing up against you."
"You tried that already, twice now," Acnologia said. "How's it gone for you then? Was she so approving of it years ago? I admit, you made great leaps since then, nephew. You've become a greater Dragon Slayer than anything this generation was capable of. You and that elder son of Igneel's."
"You were afraid of Natsu."
Acnologia's expression blankened.
"Erza and I stopped E.N.D.," Kai said. "And he was defeated by his own friends' love for him. Maybe that love that Kairi had for me will shine through today, too."
"As if my sister never loved me?" Acnologia snarled. "As if she didn't try and weaponize that against me as well?"
"I know damn well that Kairi cared for you. All of it was in vain because you're disgusting and demented. You wanted to kill all dragon-kind. Even us Dragon Slayers."
"Because you, too, had the capability to become like dragons. Just as the Dragon Queen did. Just as I did." Acnologia sighed. "Just as Kairi did."
Kai grit his teeth and pursed his lips. He'd thought about as much. If Acnologia was a human turned dragon, it would only make sense that his sister be the same way. At one point, Kairi possessed Dragon Slayer magic same as Kai. In fact, she'd probably Enchanted her magic onto him, for him to grow and evolve into.
But she purged his ability to become like her and Acnologia by merging temporarily with his Dragon Seed. Acnologia didn't seem to care, though.
"She echoes in you," Acnologia said. "You aren't our blood, but her mannerisms and spirit remain alive in you. It does sicken me. You're right. And I have to snuff out that flame once and for all, to wipe the scourge of my family's legacy from this world. You have no idea what Kairi did."
"Sounds like she was a sinner, too."
"Kairi was well-aware of the atrocities that the dragons were busily committing against everyone. Genocides of entire villages, wiping out their own kind. Slaying innocent children." Acnologia balled a fist. "I stepped in to stop them. I fought alongside humanity, and for a time, even dragons who sought to end their war."
"The Dragon Civil War."
"Kairi was with me. Prior to your damned father, Ichigo, she was renowned as the greatest of the Ice wizards in the world. She could freeze a pure dragon dead in its tracks. Her power, for a time, rivaled my own." Acnologia glared at Kai. "You see, Kairi, too, was fueled by vengeance."
He opened his palm and mists swirled out of it, ensnaring and snatching Kai, holding him in place as his mind tumbled through time and space, leaving their bodies behind.
Acnologia floated, in an ethereal form, near him. Kai drifted down toward a tiny village, where a pair of teenagers sprinted away toward the fields. A massive roar filled the entire area around them.
The boy Kai recognized immediately: Acnologia, with shorter hair and an actual expression. The girl, though, he recognized only by being able to sense it, somehow: Kairi. She had white hair and pure blue eyes. Her nails were painted a dark blue and she wore a short dress. She pulled Acnologia along.
A shadow overcame the village and in an instant the memory faded, but in a flash they were away, in a field, laying unconscious together.
"That day, it was clear to me that the dragons were no longer fighting humanity, but they treated us like game," Acnologia said. "They knew Kairi and I were born Dragon Slayers, thanks to the enhancements passed down through others from the Dragon Queen. We had a target on our backs. And we had to become stronger. Far stronger than anything you could ever muster."
Several images played before Kai, and he even sensed some of the emotion in them: fear, anger, and sadness blitzed through him as years passed before him and Kairi and Acnologia aged and matured significantly in this time, the two often leaving one another's side but then coming into contact to plan out something.
Then, they would fight back.
Kairi with her ice magic could freeze over an entire landscape while Acnologia with his magic would utterly obliterate their draconic foes. And they weren't alone. Other Dragon Slayers surrounded them.
"We thought ourselves unstoppable," Acnologia said. "I was the best and greatest among us, but Kairi held their hearts. Maybe it would have prevented what was to come…but it was necessary. There was only one way for the draconic threat to come to an end, and Kairi disagreed with me."
The next memory revealed the dragon graveyard in Crocus as it was before Acnologia intervened. A brilliant flash of light and power wiped out the dragons in the cave, an amazing display of power that all-but drained Acnologia at the time.
And there, to watch it all, stood Kairi.
"What have you done?"
"These dragons slew an innocent girl," Acnologia said, facing his sister.
"All of them?"
"The rest stood and watched. I did what was necessary."
"And your followers? Where are they, Acnologia? Why did you come alone?"
Acnologia glanced down at his hands, and a smile crept over his face.
"This wasn't about a little girl at all," Kairi said. "Don't you dare tell me otherwise. You were afraid that little girl would eventually become host to one of these dragons, that she may threaten you." Kairi tilted her head. "Like the others."
"There is no end to this threat unless one remains to contain them. Have you heard? These dragons are not our only threat. I have to gather strength, dear sister, for the problem in the north. The Dragon Gods will—."
Kairi swiped her hand and Acnologia froze in place. The memory, naturally, faded.
"That was the last I saw my sister as someone who would come to my side," Acnologia said, his ethereal form slithering by the frozen one of the memory. "But see, Kai, that even she did not stop me then. She didn't want to. After that? She refused to put me down."
Brief glimpses of several battles raged by in his mind. Acnologia fought alone against other Dragon Slayers, sometimes with Kairi nearby.
"I spared her every time, wanting her not to join me, but to know the torment that hers was an unwinnable fight. She sided with those who sought peace. I was making peace."
"By wiping out everyone and everything that opposed you."
"And tell me how threatened the world has been by dragons for centuries."
The mists around them faded and they returned to their bodies. Kai sighed, having to breathe in after spending time away from his body. His sword had faded away, too.
Acnologia tilted his head.
"When my sister vanished I thought someone else had slain her, not that she had the gall to betray me in such the way that she did. To hide you and the other children from me. I only found out centuries later through the Black Wizard what'd happened and for a long time I searched for you, never losing sight of my true goal…until I got bored of that, too."
"Now what do you want?"
Acnologia smiled. "What is my moniker."
Kai pursed his lips and grit his teeth, not at all hiding the fury latent in his heart.
"I won't let that happen. Like Kairi before me, I will stop you."
"And what makes you believe you're truly capable of that, boy? She became a dragon. And even with all that strength, she was incapable of stopping me then."
"I have no belief that I can beat you beyond the faith that others have placed in me. And that's more than enough."
Acnologia nodded.
"Then I shall destroy that faith. But first, I have to break you and end four hundred years of waiting."
Kai winced. Four hundred years? And…
He summoned his sword. Time for answers later. Acnologia shifted and the entire world shimmered around Kai before erupting in a sea of magic. He coated a thick layer of ice around him and burst forward toward Acnologia, who easily dodged his sword swing.
Acnologia punched down at Kai with such force and speed that Kai could barely dodge. Kai swung once more with his blade but Acnologia batted it away.
He charged it full with magic and attacked once more. Acnologia surged his power, holding Kai back for a moment.
"Dragon Slayer Secret Art: Ice Dragon Takeover!"
"Magic is useless, fool!"
Acnologia opened his mouth to absorb the magic but none came, as the transformation came over Kai and his power surged.
He didn't need to use excelled magic against Acnologia; he just needed to match his power.
Acnologia didn't seem to realize this, thinking Kai would move at the same speed as before. Kai, in control of his wings, had better grasp of his speed and how much faster he could move.
Acnologia punched the ground and the entire cliffside destabilized. Kai bounced between the broken parts and blasted Acnologia across the face with a powerful fist. Acnologia actually left his feet and tumbled back.
Blood dripped from his nose. "Impossible."
Kai didn't give up his pursuit, slamming his sword in the ground and using it as a vault to fling himself at Acnologia with both feet. Acnologia held his hand out to blast Kai.
Kai used his wings to spin around, changing his trajectory and position mid-air to slide against the ground and come back up to uppercut Acnologia, who blasted Kai with a Dragon Roar point-blank just as Kai's fist connected with Acnologia's jaw.
The two flew back, Kai's icy casing breaking as he tumbled away and Acnologia managing to catch himself mid-air and land.
Kai wiped the dirt from his face and Acnologia rubbed away the blood still leaking from his nose. Both combatants got back to their feet. Kai sighed, trying not to hide how much power and effort he was exerting. Acnologia still hadn't broken a sweat.
He ignored the difference in their strength and took note of the position of his sword. It didn't matter the difference in strength. Kai just needed to catch Acnologia off-guard once and it would be over.
Acnologia closed his eyes and sighed, letting his arm hang to the side. Kai didn't let his guard down, falling into a proper defensive stance.
When Acnologia opened his eyes, the world once more rippled and the winds picked up.
The Apocalypse Dragon was upon Kai before he even realized it.
"Too slow," he said, and punched Kai so hard he was sure his chest would cave in.
He would've flown far if the punch hadn't been directed downward and Kai hadn't been pummeled through so much dirt and stone. He eventually came to a halt and struggled to breathe.
Acnologia stood atop the hole and aimed his hand down.
"Goodbye."
Blue light filled Kai's vision. Still, his Takeover spell was in effect. He exerted more magic, encasing himself in the magic, then shot out of the hole just as Acnologia let his attack loose.
Kai's wings shattered but he made it out nonetheless and slid to a halt in front of Fairy Hills. Acnologia pounced, proving himself quite the fighter, even with just one hand.
Kai didn't have the strength to block his attacks, not in his current condition. His head was still in a scramble and he struggled to breathe. He just needed a second, just a minute, to collect himself.
Acnologia gave him no room, finally pushed Kai away and crushing his hand in, sending arcs of blue lightning down at Kai, who, at last, summoned his Ice-magic-charged sword to deflect the bolts of power.
"It's all you can do just to straggle along," Acnologia said. "It'd be amusing if it weren't so pathetic. And you thought you could defeat me alone? Fool!"
Acnologia charged up another attack from the sky but stopped as seven golden lights struck him and pushed him back, only to be followed by a magic circle exploding beneath Acnologia.
The dragon swiped away the debris as a figure landed between Kai and Acnologia.
"Erza and Wendy are on their way. For now, I've been sent to make sure you don't die."
Jellal Fernandes turned to Kai and gave him a thumbs-up, then returned to facing Acnologia, who smiled at his new prey.