Marco took a deep breath, gathering his focus while feeling the full weight of Kaido's seemingly endless stamina. Even without his Devil Fruit fully Awakened, his own strength was monstrous.
"I can't dwell on that now. I'll just use the system," Marco muttered, opening the system panel without hesitation.
He noted that his Conqueror's Haki was still at an advanced stage, not yet at its peak. Despite this, he had already managed to use Conqueror's Haki Infusion multiple times against Kaido, though his skill was far from perfected. Marco had no time to linger on this; he shifted his attention to his special attributes. With 8,000 remaining points, he decisively allocated them all to stamina and mental strength.
After prolonged combat with Kaido, Marco realized one thing: Kaido was fundamentally different from Big Mom. The Oni was stubborn, relentless, and unaffected by hunger, never pausing during battle, fighting to the very end.
He quickly assigned 5,000 points to stamina, raising it to 20,100, and 3,000 points to mental strength, bringing it to 13,300. The instant the points were allocated, Marco felt a rush of revitalization, his exhausted body now brimming with renewed strength.
Even Kaido, advancing towards him, paused, sensing the sudden surge in Marco's aura.
Kaido's brow furrowed. "Is this a new technique after your Devil Fruit Awakened? Your aura just surged!"
Marco didn't answer directly. He inhaled deeply, adjusting his breathing, and focused his mind.
Kaido observed silently, a flicker of envy creeping into his tone. "So this is what an Awakened Devil Fruit can do," he thought. Marco had gradually mastered Conqueror's Haki Infusion, crossing its threshold even if imperfectly. Kaido, after years of fighting, still knew nothing of Devil Fruit Awakening, the path ahead shrouded in uncertainty.
A surge of frustration welled up within him. "Is this truly my limit?"
Since defeating Kozuki Oden, Kaido's strength had stagnated. For nearly ten years, progress had nearly ceased. He had tried endless training and challenges, and aside from minor improvements in stamina and Haki, nothing else had advanced.
He knew there was a higher level in all forms of Haki—Armament, Observation, and Conqueror's Haki. Rocks had once reached that profound stage. Even Red-Haired Shanks had attained it without a Devil Fruit. Kaido's own Haki, no matter how refined, fell short, like a cup brimming to the edge, unable to overflow.
Seeing Kaido's conflicted expression, Marco sighed. "Even the Four Emperors have limits. No one is exempt."
Kaido's face darkened with the sting of disappointment. Limits existed for all, yet for him—an Emperor—there was a deep sense of injustice. Ambitions remained unfulfilled, and the title of Emperor could not contain his grand vision.
A sudden thought of resignation flashed in his mind, anger and shame coursing through him. In response, a surge of Conqueror's Haki erupted, radiating arrogance like a tidal wave. "Limits, bottlenecks, they mean nothing! I will surpass them! I will break them!"
Kaido charged once more, casting aside doubts. His spiked club wrapped in Armament Haki and Conqueror's Haki, he roared, "Great Dragon Thunder Bagua!"
Marco met the attack without hesitation, shouting, "Phoenix Flame Fire Fist!"
Their strikes collided violently in midair, blue and purple arcs of Conqueror's Haki lightning intertwining into a storm. Surrounding rubble was ground to dust, the shockwave surging outward like a tidal wave.
Both were thrown back by the impact but quickly regained footing. Kaido's voice rumbled, "Hmph, your Conqueror's Haki Infusion is improving. Soon, you may fully master it."
Witnessing Marco's growth while feeling trapped in his own stagnation filled Kaido with frustration. Though naturally gifted, whether in Haki or Devil Fruit, progress had become frustratingly elusive.
Marco, meanwhile, was pleased. His Conqueror's Haki Infusion felt increasingly natural. "Seems I'm finally getting the hang of it," he said with a teasing grin. "No wonder they call you 'Teacher Kai.' Now I see it—I can learn faster thanks to your 'bug'."
Kaido's face instantly turned crimson, fury burning in his eyes. Swinging his spiked club, he roared like thunder, "You brat! Do you really think I'm your teacher?!"