Natsu's flames ignited in the center of his palm even as he stood submerged in seawater. A ghostly blue glow reflected across his face. The fire was not crushed by the pressure of the depths. Instead, it flickered steadily, like a thin shell that forced the seawater aside. As he extended his hand forward, the fire advanced with the motion, pushing back the surrounding dark.
The giant beast's eye twitched. Its pupil contracted sharply. The suction discs around its mouth slowly closed, releasing a low, resonant hum, as if responding to something it sensed. Wendy stood atop the ice platform, both palms pressed against the surface of the water, eyes closed as she focused.
"It doesn't want to attack," she said as she opened her eyes. "The emblem is inside its body, close to the stomach sac. It's wrapped in a layer of glowing material."
Luffy broke into a wide grin and leapt straight off the ice platform into the sea. He swam up to the tip of the beast's snout and slapped it twice with his hand. "Hey! Big guy! Give us our stuff back and I'll treat you to some fish!" He threw his head back and laughed.
The colossal creature began to sink slowly. The bone spines along its back split apart to either side, revealing a passage leading into its body. The inner walls of the passage glimmered faintly, as though luminous liquid flowed beneath the surface.
Gray raised a hand and formed an ice shell, enclosing Natsu, Erza, and himself within it. The ice was semi-transparent, allowing them to clearly see the outside. Happy spread his wings, gripping Carla and Romeo with his claws, and flew into the upper aerial passage. One after another, the team entered the beast's interior.
The passage sloped downward, and the deeper they went, the thinner the air became. Natsu walked at the front, his flames burning continuously. Yet he soon noticed something was wrong. The fire began to destabilize, as though suppressed by an unseen force. He forced more magic into it, but the flames only held for a few seconds before dimming.
At that moment, a vibration pulsed through his chest. Natsu lowered his head. His guild emblem was heating up against his skin. Immediately after, a surge of warmth poured from within his body, rushing along his meridians and into his palm. The flames reignited, shifting from deep blue to blazing red-gold. The surrounding moisture evaporated in an instant.
"This is…" He clenched his fist, feeling his strength rapidly returning.
The Dual-World Bond Core had activated. The Dimensional Flame Core began absorbing ambient heat and trace energy from the environment. His fire was no longer suppressed. Instead, it became even more stable than before. Natsu pressed forward, the intense heat driving away the mucus coating the passage walls. Corrosive fluids vaporized the instant they touched his flames.
The team advanced deeper. The passage gradually widened, opening into an enormous chamber. At its center floated a crystalline mass, and within it rested the D-07 emblem, its surface emitting a faint blue glow.
Romeo took out his runic tablet and approached the crystal. The patterns on the tablet lit up, resonating with the crystal. After several seconds, cracks spread across the crystalline shell. It shattered, and the emblem slowly descended. Natsu reached out and caught it.
The Blue Flame Flower against his chest immediately grew hot, light seeping through his clothes and pointing toward the southeast. The emblem and the flower vibrated together, perfectly synchronized.
"Got it," Natsu said, slipping the emblem into an inner pocket.
The team retraced their steps and exited the beast's body. The creature slowly sealed the opening along its back and sank into deeper waters, leaving behind only a faint trail of light.
Everyone regrouped on the ice platform. Gray reinforced the edges to prevent the currents from tearing it apart. Erza stared at the metal plate embedded on the seabed below.
"Now we open the door."
Natsu nodded. He took out the D-07 emblem and inserted it into the groove at the center of the metal plate. The engraved lines lit up instantly. The entire seabed began to tremble. Sand churned, rocks shifted, and from the depths rose a colossal stone gate, towering nearly a hundred meters high, its surface carved with ancient symbols.
On either side of the gate, two stone statues over thirty meters tall slowly opened their eyes. Red light burst from their pupils. One of them raised its arm and swung it down toward the ice platform.
Gray reacted instantly, slamming both palms onto the sea surface. Three layers of ice walls formed in rapid succession. The statue's arm smashed into them. The first layer shattered immediately. Cracks spread across the second. The third barely held, but the entire ice platform was shoved backward dozens of meters.
"These things aren't affected by magic!" Gray gasped.
Natsu charged forward, red-gold flames blazing around his right fist. He leapt into the air and unleashed Fire Dragon's Wing Attack. The explosion struck the statue's chest, but it was like hitting solid bedrock. Only a scorched mark remained. The statue did not retreat even a step.
Erza switched armor. Plates covered her body as a blade of light condensed in her hand, magic surging through it. She dashed forward in an instant, the sword coated in a dark sheen, and struck the same spot on the statue's arm. A sharp crack rang out. Fractures appeared, though the arm did not break.
"Strong defense, but not invincible," she said.
Bickslow stood at the rear, a star-chart crystal glowing in his hands. His fingers moved rapidly as he pulled up underground structural data. "Found it! They're connected from behind to energy conduits supplying power from deep within the ruins. These statues are puppets, running on external energy."
"Then we cut the source," Gray said.
Leo was not present, but Wendy spoke up instead. "I can boost everyone's speed."
She clasped her hands together and softly chanted. Wind surged from all directions, wrapping around the team. In the next instant, their bodies felt lighter, their movements sharper.
Gray quickly set up ice blast traps. Beneath the statue's feet, he formed clusters of ice spikes containing compressed airflow. Once triggered, they would chain-detonate and freeze its legs in place.
"All set!" he shouted.
Natsu nodded and took a deep breath. Flames roared inside his body. With Wendy's acceleration enhancing him, he sprinted toward a crack in the ground. His right foot slammed down, his left fist shot forward, and fire blasted into the fissure. The intense heat melted through layers of rock in an instant.
A glowing conduit was exposed below, purple energy flowing visibly along its surface. Natsu increased his output, the flames burning relentlessly. Within seconds, cracks spread across the conduit's outer shell. Energy began to leak.
"Now!" Erza leapt high and switched to a new set of armor. The blade was pitch-black, its edge glowing red with condensed magic. She dove straight down, blade aimed at the fracture point.
At the same time, Natsu unleashed a long-range stream of fire. His flames wrapped around her blade, merging with her slash. Fire and blade tore through the air together and struck the conduit with devastating force.
Crack.
The conduit snapped. Purple energy erupted outward before rapidly dissipating. The statues froze mid-motion. The red light in their eyes flickered several times, then faded. One statue's knees buckled, and it crashed down as its massive body began to crumble.
Dust billowed. Fragments fell into the depths.
At the instant the statue collapsed completely, a fissure opened in its chest. A projection of light spilled out. Within it stood a black-robed figure atop a high platform, back turned to the viewer. His voice was low and cold.
"Intrusion detected. Defense protocol compromised. Guardian program upgrading. The time draws near."
The projection vanished. The statue shattered into nothingness.
Natsu stared at the now-open entrance, his fist clenched. Erza sheathed her blade and walked to his side.
"The door is open."
Gray checked the stability of the ice platform and confirmed it could hold a little longer. Wendy closed her eyes again, sensing the surroundings. Her brow furrowed.
"There's more movement inside."
Bickslow brought up his star chart. Multiple energy signatures were visible within the ruins, slowly shifting positions. Romeo hugged his runic tablet, recording the data as lines of information refreshed nonstop.
"More than one guardian," he said.
Happy circled overhead, confirming there were no immediate threats nearby. Carla's ears twitched as she spoke in a low voice. "The temperature is dropping."
Before her words even faded, tremors echoed from deep within the ruins. Red light flared again from the cracks in the ground.
Erza shifted back into a combat stance. Frost spread across Gray's hands as ice blades formed in his palms.
Natsu reached into his chest pocket and touched the Blue Flame Flower. Its heat was stronger than before, nearly scorching. He lifted his head toward the darkness beyond the stone gate. Flames danced in his clenched fist.
"No matter what's waiting inside, we're going through."
He took a step forward, fire illuminating the darkness ahead.
Within the gate, another stone statue slowly rose to its feet. Its eyes glowed red as its arm lifted, palm aimed directly at the entrance.
Suddenly, Natsu's flames began to violently waver.