In the One Piece world, the distinction between swords and blades was pretty blurry. Someone who used a blade could still be called a swordsman or even achieve the title of World's Strongest Swordsman.
But that didn't mean swords and blades were the same thing. Not even close.
Blades, katanas, sabers, those types, emphasized slashing power. One sharp edge, designed to cut through your enemies with great force.
Swords, on the other hand, were double-edged weapons with sharpness on both sides. Sure, you could slash with them, but their real strength was in thrusting and piercing attacks.
And because of that double-edged design, swords were naturally more flexible and agile than blades. They could flow, redirect, adapt. But that versatility came with a trade-off, in pure power contests, swords didn't have the advantage.
Marcus frowned as he studied Saga, whose body was clearly being puppeteered by whatever malevolent force resided in the Shichiseiken.
"You blade users who switch to swords," he muttered, "do you really think you can just brute force your way through everything?"
The complaint slipped out before he could stop it. The truth was, under Saga's control, or rather, under the sword's control of Saga, the Shichiseiken was being wielded like a damn cleaver. No finesse, just brutal swings.
Of course, Saga couldn't respond. He stared directly at Marcus without blinking, and the force behind his strikes kept increasing.
The Shichiseiken and Marcus' diamond sword clashed again, sending sparks flying in every direction.
The power coming from Saga was steadily growing, like the sword was gradually unlocking more and more of its wielder's potential strength. And with each collision, Marcus could feel the attacks were evolving. It was like Saga was slowly remembering how to properly use a sword, or maybe the Shichiseiken itself was teaching him through combat.
Marcus actually found himself excited by this development. Not only did it make the fight more interesting, but he could learn from watching the techniques unfold in real-time.
But as his palms started going numb from the repeated impacts, a concern emerged. Sure, he wanted to see what Saga's final form would look like when the sword fully awakened, but at this rate, he might not have the stamina to keep up long enough to witness it.
I really didn't want to use my Devil Fruit abilities for this, he thought. A pure sword duel should be about skill, not supernatural bullshit. But if I want to keep up...
His arm suddenly swelled, and his power exploded in an instant. Where Saga had been maintaining the advantage in their blade lock, he was now sent flying backward, skidding across the ground for dozens of meters before catching himself.
Taking advantage of the brief opening, Marcus pulled out a golden apple and bit into it. The fruit flooded his system with healing energy, repairing the micro-damage to his muscles and joints.
Then he pulled out a strength potion and downed it in one gulp. The liquid burned going down, but immediately he felt raw power coursing through his veins.
This was his first time actually using potions in combat, and he had to admit, the sensation of overwhelming strength was intoxicating.
"Alright, round two!" He grinned.
BOOM.
The ground beneath his feet exploded as he launched forward, stone fragments scattering in every direction.
CLANG.
When he reappeared, he was already at Saga's side, his diamond sword thrusting forward in a piercing attack aimed at his opponent's center mass.
Saga hadn't even seen the strike coming, Marcus had moved faster than perception. But the Shichiseiken moved instinctively anyway, shifting horizontally to block the thrust.
The wind seemed to lag behind their movements, only now catching up and creating a violent shockwave that expanded outward from the point of impact.
Using Marcus and Saga as the epicenter, the pressure wave flattened the grass in a circle. Dust and debris were blown away, and even some of the smaller rocks went tumbling.
Zoro, who was currently engaged with Toma about twenty meters away, noticed the explosive clash. He turned his head just in time to see the aftermath and couldn't help feeling impressed.
Marcus' growth rate was even more insane than he'd thought.
When they'd first met back, Marcus had been a complete amateur who didn't even know how to properly grip a sword or take a fighting stance. His physical conditioning had been terrible, all that time spent gaming had left him with poor reflexes and stamina. If it hadn't been for his weird Devil Fruit abilities, he probably would have been seriously injured by Kuro.
But how long had it been since then?
Not only had his physical abilities improved dramatically, but his mastery of swordsmanship was developing at a frightening pace. The guy was a natural learner, you showed him something once, and he'd internalize it immediately. Most techniques didn't require a second explanation.
"If I don't train twice as hard, he's gonna surpass me." Zoro muttered, feeling competitive pressure building in his chest.
Toma, despite being corrupted by the cursed energy, had gradually been regaining his rationality. His body, however, kept attacking automatically. "Your friend is in danger."
Zoro crossed both his swords and blocked Toma's strike, then gave a dismissive snort. "That guy? He's not even fighting seriously yet."
Haki and the concept of "breath," Marcus had been the one to articulate those ideas for the crew. And right now, he could tell that Marcus hadn't even started using Haki. He was fighting purely with physical strength, technique, and a bit of Devil Fruit augmentation.
Toma didn't respond. Though the cursed aura was still affecting him, the corruption had stopped spreading. In fact, the demonic energy's grip on him was slowly weakening, one of the main reasons he was regaining his sanity.
At the same time, he could feel feedback coming from the Shichiseiken. Some kind of emotional resonance from the cursed blade. And that sensation made him regard Marcus not just as a threat, but as something terrifying. He couldn't explain why. For a moment, he even suspected it was just his imagination playing tricks on him.
Then it happened.
Saga's sword grip suddenly shifted. He stopped wielding the Shichiseiken like a crude cleaver.
Marcus noticed the change immediately.
Saga was redirecting energy now, transferring Marcus' own force and using it against him.
This was exactly what Marcus had been hoping to see. He kept his eyes locked on Saga, not daring to blink and miss any detail of the technique.
He lowered his body into a more aggressive stance and shot forward like a striking viper. His diamond sword stuck to the Shichiseiken like glue, maintaining constant contact as he tried to pressure Saga with pure overwhelming force.
Faced with overwhelming strength, Saga remained perfectly calm. The Shichiseiken flowed lightly through the air, creating after-images as it moved.
Marcus was putting ten parts of force into each attack. But with just a subtle twist of Saga's wrist, seven of those parts were effortlessly redirected, or absorbed.
And it didn't end there. The energy Saga had neutralized didn't just vanish into thin air. He spun his body and redirected those seven parts of force, combined with his own full strength, straight back at Marcus.
The strike was aimed precisely at Marcus' throat.
Speed, technique, and power, all three elements were displayed perfectly in that single instant of motion.
For almost anyone else in the East Blue, that blow would have taken their head clean off their shoulders. But unfortunately for the cursed sword, its opponent was Marcus.
The sharp edge of the Shichiseiken pressed against Marcus' neck. The blade met his skin and simply... stopped. It couldn't pierce through. Like it had hit a wall of solid diamond.
"So this is real swordsmanship," Marcus said. "Magnificent."
He wasn't being sarcastic. He truly appreciated what he'd just witnessed.
It wasn't that he hadn't reacted to Saga's technique, his mind had registered the attack perfectly fine. But even though his brain understood what was happening, his body hadn't been able to twist or block in time.
Normally, he would have managed to both perceive the attack and respond to it.
But Saga's sword hadn't just borrowed his momentum. It had also used the redirected energy to shift Marcus' center of gravity, making it physically impossible to recover fast enough for a counter or defense.
This was what real swordsmanship looked like when executed by someone who'd truly mastered the art.
Saga's purple-glowing eyes widened slightly, clearly surprised that his attack hadn't decapitated Marcus. He immediately leaped backward, putting distance between them, eyes fixed intently on Marcus as he reassessed his opponent.
Marcus found himself slightly surprised by the reaction. Had Saga regained his rationality?
But then he noticed Saga's current stance and the way the Shichiseiken was being raised into position.
What finally took shape before his eyes was a textbook classical fencing stance, the kind you'd see in European sword manuals from centuries ago.
Saga's body turned slightly to the side, presenting a smaller target.
One hand was positioned behind his back.
The other hand extended forward, sword pointing straight at his enemy.
Marcus blinked in surprise. He'd seen this style before in movies. Noble swordsmanship, some called it. The rapier tradition.
This particular branch of swordplay emphasized speed and agility over raw power, using quick thrusts as its primary form of attack. Light on the feet, deadly at the tip.
But that raised a question: where had Saga learned this?
He glanced sideways at Zoro, who had clearly noticed the same thing.
This definitely wasn't something Koushirou would have taught at his dojo. The old swordsman from Wano had been traditional to his core, katanas all the way, none of this Western fancy footwork.
So either Saga had learned this somewhere else entirely, or...
Marcus' eyes narrowed as he studied the Shichiseiken more carefully.
From the raw power clash at the beginning to this display of refined technique... was this how the sword elevated its wielders? By channeling centuries of combat experience through whoever held it?
Before he could think about it further, Saga moved.
The Shichiseiken swept downward, and a flying slash erupted from the blade, tearing through the air straight toward him.
Marcus wasn't surprised. Anyone who'd reached the level of a swordsman could produce flying slashes. It was basically a requirement for the title.
He'd been working on his own version ever since that all-out strike back on Drum Island.
Honestly, it wasn't that complicated once you broke down the mechanics. Flying slashes were basically just Tempest Kicks infused with Haki. The Haki let the slash travel farther and hit harder, maintaining its cutting power over distance.
His attack on Drum Island had been just overwhelming power compressed into a single strike.
"Flying slashes look impressive," Marcus said as his diamond sword became coated in Haki, "but they're not as deadly as people think."
He swung.
A brilliant blue-white slash shot forward from his blade, cutting through the air with a distinctive whistling sound.
The two attacks collided midair. Cracks spider-webbed outward from the point of impact.
CRACK.
The flying slashes struggled against each other for a brief instant, then veered apart.
A clear line now divided the battlefield.
On one side stood Saga in swirling purple-black energy, his hair whipping around his face like he was caught in a windstorm.
On the other side stood Marcus, perfectly calm and steady, showing no signs of strain.
"Time's almost up," he said, glancing at his status bar. His recovery period was about to end, full stamina restoration, and more importantly, his Haki reserves would be completely refilled. "If this is all you've got, you're going to lose."
Saga didn't respond. His eyes remained fixed on Marcus, but there was no hint of understanding in them. The sword was still in full control.
Marcus didn't wait for an answer. He gripped his diamond sword with both hands, and channeled all his strength to one point.
Armament Haki wrapped around the diamond blade, and then, purple-black lightning began crackling along its length.
The sight left everyone present stunned.
Even Zoro was captivated, unable to tear his eyes away. "That's—"
Saga's body tensed. The Shichiseiken responded to the threat by erupting with even more cursed energy, pouring power into its wielder's body.
The ground beneath Marcus' feet began to crack.
"Huff... I haven't come up with a proper name for this yet. Still working on the technique. So for now, let's just call it... a basic thrust."
The words had barely left his mouth when he vanished.
The ground beneath where he'd been standing exploded a split second later, stone chunks flying upward and backward as the force finally caught up with his movement.
CLANG!
Sword tips collided.
The sonic boom that followed was deafening. The ordinary Marines who'd managed to stay on their feet were blown backward, tumbling across the ground.
Several didn't get back up, knocked unconscious by the sheer force of the pressure wave.
CRACK. CRACK. CRACK.
Fissures spread outward like lightning bolts, chunks of rock breaking free and tumbling into the newly-formed cracks.
When the dust finally began to settle, only one figure remained standing in the center.
Marcus slowly lowered his sword, rolling his shoulders. He'd put everything into that thrust.
Saga had been sent flying backward by the impact, tumbling end over end before crashing to the ground nearly fifty meters away. He wasn't moving.
Marcus walked slowly toward where Saga lay unconscious.
"Not bad for a cursed sword. Didn't even chip it. If the wielder's body had been stronger, they might have actually been able to take that hit without getting knocked out."
The Shichiseiken was still clutched in Saga's hand, and the cursed aura around it was... angry.
It had been overpowered by a simple thrust attack. And worse, it had been held back by the physical limitations of its wielder.
The ghostly energy began surging wildly, lashing out in all directions. The corrupted Marines who'd been knocked down were starting to get back up, stumbling toward the sword like zombies drawn to fresh meat.
The Shichiseiken wasn't done fighting. It was going to use these guys as new hosts, throwing bodies at Marcus until something stuck.
"Yeah, not happening."
Marcus used Soru to cross the distance in an eyeblink. He crouched down next to the cursed blade.
Zoro, who'd been helping Toma stay upright, noticed what Marcus was doing. "Wait, don't—"
Too late.
Marcus' hand closed around the Shichiseiken's hilt.
The cursed energy immediately found an opening and poured into him, trying to overwhelm his mind and seize control of his body.
For about half a second, the sword thought it had succeeded. Then the Shichiseiken vanished completely, sucked into Marcus' inventory. The raging cursed aura disappeared with it.
The corrupted Marines collapsed, hitting the ground all at once.
Toma suddenly felt the foreign energy sustaining him drain away completely. His head started spinning, and his vision blurred.
"What—"
Then his eyes rolled back and he collapsed, unconscious before he hit the ground.
Zoro stared at the scene. "What did you just do?"
Marcus stood up, brushing dust off his pants. "Put it in my inventory."
Zoro blinked several times, trying to process that explanation. He knew Marcus had some kind of storage ability, the guy could pull out food, weapons, and building materials from apparently nowhere. But storing a cursed sword that was trying to possess people?
"Your Devil Fruit ability really is something..." he finally said. "Even that cursed energy couldn't affect you?"
He looked down at Saga's unconscious form. Without the ghostly energy supporting him, the guy looked terrible, almost skeletal, with his injured hand clearly untreated beneath hastily-wrapped bandages.
"We need to—" He was about to ask for help healing his friend when a golden apple and a barrel of milk suddenly landed in front of him
Marcus was already walking away, heading toward where the other Marines were starting to regain consciousness. "Get him stabilized. I'll handle the cleanup."
Zoro didn't argue. He knelt down beside Saga and got to work, feeding small pieces of the golden apple to his unconscious friend while preparing the milk for treating the cursed energy's lingering effects.