The group moved carefully through the silent ruins, the air still heavy with the remnants of the battle they had just fought. The dust from the fallen creature had barely settled, but Tanjiro's mind was already racing with new revelations. Every step they took in this ancient city seemed to uncover another layer of mystery—a deeper understanding of what had come before them, and what still lay ahead.
Nezuko walked silently beside her brother, her eyes constantly scanning their surroundings for any new threats. Though the cursed warrior they had faced was gone, she knew that this place still held many dangers. The ancient energy that pulsed through the ruins was unsettling, and she could feel it tugging at something deep within her.
Gon, always curious, seemed more excited than concerned. "That fight was incredible! I've never seen a demon like that before. Do you think there are more of them around here?"
Killua, ever the pragmatist, shot him a glance. "Probably. If this place is full of remnants of the ancient kingdom, there are likely more cursed beings still wandering around." He paused, his silver eyes narrowing. "But something's been bothering me."
Tanjiro looked at Killua, noticing the intensity in his expression. "What is it?"
Killua gestured to the remains of the city around them. "This place—it's ancient, yes. But it feels like something's still alive here. Not just the demons or cursed warriors, but the city itself. There's an energy I can't quite place."
Gon's grin widened. "You think the city is alive?"
Killua shook his head. "Not in the way you're thinking. But something is feeding power into this place. Maybe it's connected to that god we saw in the murals. Or maybe…" His voice trailed off, as if the thought was too unsettling to voice fully.
Tanjiro considered Killua's words carefully. The ancient warriors had mastered breathing techniques in ways that surpassed anything the modern Demon Slayer Corps could even dream of. And yet, their civilization had crumbled, cursed by the very god they had tried to control. The question lingered in his mind—what was left behind? And how did it still hold such power over this place?
Nezuko hummed softly, her gaze locking onto a nearby building that had caught her attention. The structure was larger and more intact than most of the other ruins they had seen, its stone walls adorned with intricate carvings. Unlike the crumbling houses and broken pillars around it, this building seemed preserved, as though it had been untouched by time.
Tanjiro followed her gaze, his breath catching as he noticed the same thing. "That building… it looks important."
Killua raised an eyebrow, his interest piqued. "You're right. It's still standing while everything else around it has fallen apart. There's definitely something in there."
Without hesitation, the group made their way toward the structure, their steps cautious but determined. As they approached, they could see the carvings on the walls more clearly. They depicted scenes of warriors in battle, much like the murals they had seen before, but these carvings showed something different. There was a central figure in every scene—a king, standing tall and proud above his soldiers.
Gon ran his hand along the carvings, his brow furrowed. "This king… he looks like he's leading them into battle. But he doesn't have the same twisted features as the demons we saw in the other murals."
Killua studied the carvings closely. "That's because this was before the curse. This king must have been the ruler before everything went wrong."
Tanjiro nodded, his eyes tracing the lines of the king's face. "He looks like a great warrior. But if he's the one who led his people to ruin, then his strength alone wasn't enough to save them."
Nezuko, standing beside her brother, pointed to another part of the carving where the king was depicted holding a large, ornate sword. The sword seemed to radiate light, its blade cutting through the darkness surrounding the warriors.
Tanjiro's heart skipped a beat. "That sword… it looks like it was forged with the power of the breathing techniques."
Killua glanced at him. "You think the king used the ancient breathing techniques?"
"I think it's more than that," Tanjiro said quietly. "The king might have been the first to master the true form of breathing. If this sword was created using the same techniques, it would have been a weapon of immense power."
Gon's eyes widened with excitement. "Maybe it's still here! If we can find it, it could help us fight whatever's coming."
Killua, always cautious, shook his head. "Don't get too excited. If that sword still exists, it's probably guarded by something powerful. We need to be careful."
The group entered the building, their footsteps echoing in the silence. Inside, the air was cool and still, untouched by the decay that had overtaken the rest of the city. The walls were lined with more carvings, depicting the rise and fall of the kingdom. But at the far end of the room, something caught their attention.
A large stone sarcophagus stood in the center of the chamber, its surface engraved with the same symbols they had seen throughout the city. At the head of the sarcophagus, a statue of the king stood watch, his face stern and his hand resting on the hilt of his sword.
Tanjiro felt a chill run down his spine. "This must be the king's tomb."
Nezuko stepped forward, her eyes fixed on the statue. She could feel the power radiating from the stone, as though the king's presence still lingered even after death. The energy in the room was thick, almost suffocating, and Tanjiro could sense that they were standing on the threshold of something monumental.
"We're close," Tanjiro said softly. "The answers we've been looking for are here."
Killua moved closer to the sarcophagus, his eyes scanning the symbols. "These carvings… they're different from the ones outside. It looks like a combination of breathing techniques and something else."
Gon peered over Killua's shoulder. "What do you mean?"
Killua's expression grew serious. "The breathing techniques here are advanced, beyond anything we've seen. But there's another element—something darker. It's almost like the king wasn't just using breathing techniques. He was using the power of the god that cursed him."
Tanjiro's eyes widened. "You mean… the king tried to control the god's power?"
Killua nodded. "That's what it looks like. He didn't just use the breathing techniques to strengthen his body—he was trying to harness the god's energy to become even more powerful. But that's what led to his downfall."
Gon frowned, his usual optimism dimming. "So, the king's greed for power destroyed him?"
"It wasn't just greed," Tanjiro said quietly. "He wanted to protect his kingdom. But in trying to control something beyond his understanding, he doomed them all."
Nezuko, standing beside the sarcophagus, reached out and gently touched the stone. The air around her seemed to pulse, the energy growing stronger as if responding to her presence. Tanjiro felt the hair on the back of his neck stand on end. Something was happening.
Before they could react, the ground beneath their feet began to tremble. The air grew thick with pressure, and the room was filled with a low, rumbling sound. Nezuko's eyes widened in alarm, and she stepped back from the sarcophagus as the stone lid began to shift.
"Get ready!" Killua shouted, electricity crackling around his body as he prepared for whatever was coming.
The sarcophagus slid open with a loud, grinding noise, and a cloud of dust billowed out into the room. Tanjiro raised his sword, his heart pounding as he waited to see what would emerge.
From the depths of the sarcophagus, a figure rose—tall and imposing, dressed in the armor of the ancient king. His eyes glowed with a faint red light, and in his hand, he held the very sword depicted in the murals. The blade shimmered with an unnatural light, its edge razor-sharp and filled with the power of the ancient breathing techniques.
But the king's face was twisted, his once-noble features marred by the curse that had taken hold of him. His body was strong, but his soul had been consumed by the dark power he had tried to control.
"This must be…" Tanjiro whispered, his voice trembling with both fear and awe, "the Forgotten King."
The king's glowing eyes locked onto Tanjiro, and a deep, menacing voice echoed through the chamber. "You have come seeking power… But you will find only death."
The King's Challenge
Without warning, the Forgotten King lunged forward, his sword slicing through the air with terrifying speed. Tanjiro barely had time to react, raising his blade just in time to block the attack. The force of the blow sent him skidding backward, his arms trembling from the impact.
"He's strong!" Tanjiro gasped, struggling to regain his footing.
Gon, always quick to act, charged at the king, his fists glowing with nen. "Jajanken: Rock!" he shouted, delivering a powerful punch aimed at the king's chest.
But the king moved with unnatural speed, dodging the attack with ease. He swung his sword in a wide arc, forcing Gon to leap back to avoid being cut down.
Killua zipped around the king with Godspeed, his movements a blur of electricity. "We can't let him control the flow of the fight!" he called out, launching a flurry of attacks aimed at the king's weak points.
But even Killua's lightning-fast strikes couldn't penetrate the king's defenses. The ancient ruler moved with precision, blocking and countering each attack with the skill of a warrior who had mastered every form of combat.
Nezuko growled, her eyes glowing with a fierce light as she leaped into the fray. Her claws slashed through the air, striking at the king with incredible force. But the king's sword met her attacks with ease, deflecting her blows and sending her skidding across the stone floor.
Tanjiro gritted his teeth, his mind racing. The king was unlike any opponent they had faced before—he was a warrior who had mastered the true form of breathing techniques, and his strength was beyond anything they could match.
But Tanjiro refused to give up. He could feel the power of the ancient techniques pulsing within him, waiting to be unlocked. If he could tap into just a fraction of what the Forgotten King had achieved, he might be able to stand a chance.
With a deep breath, Tanjiro steadied his mind, focusing on the rhythm of his breathing. The knowledge he had gained from the ancient murals and the tablets filled his thoughts, and he began to channel that energy into his body.
"I won't let you destroy us," Tanjiro whispered, his voice filled with determination. "I'll protect everyone."
With a burst of fiery energy, Tanjiro lunged at the king, his sword blazing with the power of Hinokami Kagura. "Hinokami Kagura, Flame Dance!" he called out, his blade striking with incredible speed and precision.
The king raised his sword to block the attack, but Tanjiro's strike cut through the air with such intensity that it forced the ancient ruler back. The fiery energy of Tanjiro's breathing technique clashed with the king's dark power, creating a brilliant explosion of light and shadow.
For a moment, the king faltered, his cursed form flickering as if struggling to maintain control.
"We can do this!" Tanjiro shouted, his heart pounding with renewed hope. "Together, we can defeat him!"
Gon and Killua nodded, their faces filled with determination. Nezuko, growling fiercely, charged forward once again, her claws glowing with demonic power.
The battle was far from over, but with the power of the ancient breathing techniques at their side, Tanjiro and his friends would fight to the very end.