But of course, Oster wasn't fighting Rosgall at full strength.
Ron and the others hadn't dealt any decisive damage during their earlier fight with him, but their attacks had forced Oster to burn through an enormous amount of aura. Even without being wounded, just maintaining that level of output had drained him. Especially after the effect of "pain split"
He long since passed his peak condition.
To put it plainly: in Naruto, Kakashi could barely manage one or two Chidori before running dry on chakra. If he used three, it would completely push his body past its limits.
Was that version of Kakashi still Kakashi at full strength?
Obviously not.
Oster was in the same situation—though not quite as extreme.
Based on Ron's estimate, their previous battle had forced Oster to use up about 75% of his aura. Only a quarter remained by the time Rosgall stepped in.
That drop in power explained why Rosgall had been able to perform so well.
Ron quietly considered something.
"If Rosgall hadn't shown up… could I have beaten Oster alone?"
He thought for a moment.
Yes—possibly.
"Oster's ability seems to lean heavily toward Conjuration. He can manifest snakes... and while he hasn't used ranged aura blasts, that likely rules out Emission as his core type."
"Everything revolves around the snakes."
"They come in three varieties."
"The first type are the small snakes—like the ones that ambushed me. Not powerful, but very stealthy."
"The second type are the large snakes—used against Chrollo, and the ones that badly injured Franklin."
"A single one of those is equivalent to an A-rank Nen user."
"From what I've seen, he can control two of those simultaneously."
"And then there's the giant serpent."
"It must've been over a hundred meters long, several meters thick. Its power and defense are in a completely different league."
"And Oster hides himself inside it."
"That's his ultimate ability—offense and defense combined."
"But the cost to maintain it must be absurd."
"It reminds me of Sasuke's Susano'o—the defensive form. Powerful, but draining."
Ron went deeper into his analysis.
"The small snakes aren't a threat to me."
"The large ones—Natsu and Sasuke can hold them off."
"But against the giant serpent, I'd need to avoid direct confrontation. A war of attrition would be the only answer."
"I'd have Natsu and Sasuke keep him busy… while I chip away at his strength with Rotten Life Blade, Killer Queen, and Lampent."
Rotten Life Blade was designed to drain opponents over time.
And Lampent's special skill—Pain Split—was devastating. Once activated under the right conditions, it could immediately cut an opponent's aura reserves in half.
That kind of sudden drop almost guaranteed a fatal opening.
"If it turned into a prolonged battle… I'd need at least half a day."
"The first part of the fight would just be about stalling."
"Only after enough exhaustion sets in can victory be decided."
"Oster ranks at the very top of A-rank Nen users."
"But so do I."
...................
.........
.
Elsewhere, the Phantom Troupe had gathered together.
They had taken over a private clinic. The doctors inside were treating the injured—Bonoleno , Nobunaga, Franklin, and Phinks were all in critical condition.
The others had minor injuries.
Only Chrollo, Hisoka and Hooker remained in decent shape.
Shalnark's body had been placed in a separate room.
Feitan, Chrollo, Pakunoda, Hooker, and Hisoka were waiting just outside the operating room.
"Hisoka," Chrollo said quietly, "any updates from the Underworld Mafia?"
Hisoka shook his head. "Nothing."
"Good."
Chrollo let out a slow breath.
"Honestly, there shouldn't be anyone stronger than Oster in the Mafia. If there were, they'd be more than just a criminal syndicate…"
Oster's strength had shocked him.
But after a thorough analysis of the battle, Chrollo realized something—if they'd had accurate intel, and the entire Troupe had acted in full coordination, they could have brought him down.
Their losses weren't purely due to power disparity. They'd walked into every fight blind.
Uvogin had died because no one understood the Spider-Man's ability.
Kortopi was killed because no one knew what the white-haired youth could do.
Shalnark had gotten careless—never imagining the black-haired one could survive that final strike.
Oster's conjured serpent had been overwhelming. But clearly, it came at a cost.
If he really was so unstoppable, why flee?
If he could've wiped them all out, why didn't he?
The fact that he left meant he couldn't win without paying too high a price.
That was Chrollo's conclusion.
He also suspected the reason the Underworld Mafia feared Meteor City was because they couldn't completely overpower its Nen users. At least not the high-end ones like Chrollo or Hisoka.
Taking everything into account, Chrollo now had a rough estimate of Oster's power level.
Though it wasn't perfect—he didn't have all the facts.
But Oster was already gone.
So even if his analysis had gaps, it wouldn't change anything now.
Chrollo's gaze shifted.
All eyes turned toward Hisoka.
"Hisoka," he said, voice low but firm, "mind explaining something?"
"Why, in the last fight with the Mafia's six genetically altered elites… did you hold back your real power?"
Pakunoda's voice cut in, sharp with anger. "If you and Hooker had handled your opponents sooner, Uvogin and Kortopi would still be alive. And Shalnark might have survived too."