With the help of Observation Haki, Karl quickly reached the hall where Gecko Moria was.
"Heh-shi-shi-shi… a shadow. A new one?"
Gecko Moria noticed Karl at once. Staring at the shadow cast by the lamplight, he let out his trademark laugh and said with approval, "If you got past Absalom and Perona's 'tests' to find your way here, you're no ordinary brat."
"Name yourself, kid."
"Karl, the man who's about to beat you," Karl said, granting him that much courtesy.
"Heh-shi-shi-shi… I haven't moved in ages. Let 'him' be your opponent."
Gecko Moria clearly didn't put Karl in his eyes.
Years ago in the New World, being crushed by Kaidō shattered his fighting spirit; he'd even lost the Haki all true elites wield. Unable to sense how terrifying Karl's aura was, he laced his fingers behind his head; his once "slim" body now ballooned like a blimp, and he lounged lazily on a custom long sofa. A black-violet shadow unfurled from him, taking the shape of a shadow-duplicate Gecko Moria that stepped in front of Karl.
"This is going to go badly for you," Karl warned, frowning.
"Heh-shi-shi-shi… go badly for me?" Gecko Moria replied with a playful curl of his lip.
"You're getting sent flying."
Almost the instant Moria spoke, Karl blurred around the shadow and sprang into the air to appear right before him.
Under Gecko Moria's widening eyes, Karl threw what looked like a feather-light punch.
Boom—crack-crack-crack-crack-crack.
His fist sank into Moria's gut, which was larger than Karl's entire body, and drove it inward.
A terrifying backblast poured out of Gecko Moria, shattering the sofa, punching through the floor, spiderwebbing the surrounding walls.
The bulbs overhead blew out in unison like a scene from a horror film.
"Guh…"
Blood sprayed from Moria's mouth as that single punch blasted him from the top-floor hall down into the first-floor hall and buried him in the floor.
Such was the terror of one blow.
Facing a Warlord-class foe for the first time, Karl didn't hold back.
With his body freshly through a second evolution, he unleashed his normal-state power for the first time.
Without even using Haki, Karl's strike became an air cannon of pressure that bored through several floors and hammered Gecko Moria into the ground.
No doubt, if that fist had landed on a small mountain, the mountain would have exploded in an instant.
But in this world, the strong are almost uniformly monstrous; even someone who can step dozens of times in 0.36 seconds to "shave" into an instant burst of motion doesn't rank among the top.
Though Moria had lost his Haki since his defeat to Kaidō and, over the years, his agility and battle edge, he was still Warlord tier, with a freakish body to match.
Taking Karl's punch head-on, he only spat blood and was seriously but not fatally hurt; he didn't black out.
"Damn brat…"
That one punch knocked the contempt right out of him and filled his aggro bar to max.
Gecko Moria clawed himself up, glared at Karl dropping down from the upper floor, and drove his shadow to attack. "Kage Tsuno-Spear!"
The shadow caster lunged as a long spear, its piercing power overwhelming, thrusting straight for Karl.
"Good technique."
Anticipating it with his senses, Karl's eyes lit.
His palm took on the telltale black sheen of Armament Haki, the kind only true rulers or former users can perceive, and he caught the shadow spear head-on, a thrust that could skewer a giant in an instant.
"Armament Haki!"
Gecko Moria's eyes bulged. "A Haki user showing up in my playground… who the hell are you, kid?"
Instinctively he suspected an old enemy had sent Karl to assassinate him.
Like Conqueror's Haki, those who wield Haki in the first half of the Grand Line are vanishingly rare.
"I told you, the one who'll defeat you."
Karl released the spear, tilted forward, and vanished again in a streak.
"Don't get cocky."
Haki lost or not, Moria's eye could still track Karl's movement.
The shadow caster snapped back to his side as if by teleport, then split into a cloud of bat-shaped shadows, a sweeping strike meant to catch Karl.
"Too slow."
Karl simply accelerated out of the bats' range and drove his right fist at Gecko Moria again.
"Doppelman."
Having tasted the power of that fist, Moria didn't dare eat a second one head-on.
Years of soft living had robbed him of his old agility; he could only rely on his fruit to swap places with his shadow.
The bat swarm reknit into the shadow caster in Moria's spot to take Karl's punch.
Boom.
The air-cannon shockwave punched clean through the shadow caster.
A heartbeat later, the wound sealed and the caster stood whole.
"Excellent ability."
Karl turned as Moria recalled the caster and sent the bats swarming again, and he offered a second, sincere appraisal.
No question, the Shadow-Shadow Fruit is top-tier among Paramecia.
It was the pillar of Moria's rise at the dawn of the Great Pirate Era, and why even after losing to Kaidō he was invited to be one of the Seven Warlords of the Sea.
Had he not been broken after that battle, sinking into apathy, neglecting his own strength and pinning his hopes on those pitiful zombies, he would not have fallen to the weakest of the Warlords, a shame among them, beaten even by a Straw Hat with no Haki to speak of.