Finn exhaled slowly and opened his eyes.
Konoha spread out below him from the face of Hokage Rock, bathed in flat morning light. He wasn't interested in the view. He looked down at his wrist instead.
The three magatama marks were fainter than yesterday. The cursed seal was consuming itself, bit by bit, its stored natural energy burning away against his body's own vitality. Orochimaru had called it a key. When the last of those marks finally vanished, the door it had cracked open would either swing wide or slam shut, and Finn would know definitively which.
His working guess: he wouldn't need to ask for a second bite. He'd figure it out on his own. Going back to Orochimaru with his hand out would be embarrassing, and Finn still had some pride about that sort of thing.
He tucked the wrist back across his knee and returned to thinking.
His understanding of natural energy — senjutsu — had deepened over the past weeks, but it remained stubbornly incomplete. Sitting on this rock, breathing in the ambient charge of the world around him, he'd had enough time to form a rough taxonomy. As far as he could tell, people who wanted to fully master Sage Mode fell into two broad categories, and the difficulty was entirely different depending on which one you were.
The first category was ordinary people. Jiraiya was the clearest model.
For someone like him, the challenge was architectural. The ratio of natural energy to physical and spiritual energy that the human body could safely sustain was narrow. Push past it and the body began to fossilize — stone-frog syndrome, slow petrification from the outside in. Jiraiya had never fully solved this problem, which was why faint toad-like features still surfaced around his eyes and face when he entered Sage Mode. He'd worked around it by having Fukasaku and Shima ride his shoulders, feeding him natural energy from outside so his own system didn't need to sustain the integration continuously. A workaround, not a solution. Effective enough on the battlefield, though.
The second category was people like Uzumaki Naruto, Senju Hashirama, and Finn himself.
Their constitutions were fundamentally different. Extraordinary vitality, deep physical reserves, a body that could absorb and hold a volume of natural energy that would destroy an ordinary person outright. For them, the architectural problem barely existed. Their bodies didn't resist the integration.
The difficulty, for this second category, was something else entirely: sheer quantity.
Finn turned the concept over. If the ratio Jiraiya needed to fill was one unit — and Jiraiya only had to fill it once — then the volume of natural energy Finn's body required to reach that same proportional saturation was closer to one hundred. The reservoir was vastly larger. The ratio itself was identical. But filling a reservoir a hundred times the size took a hundred times the effort, and there was no shortcut to that particular problem unless you had access to the accelerant materials the three sacred places kept to themselves. Toad oil. The sacred preparations of Myoboku Mountain. Something like that.
He didn't have any of it right now. So he worked with what he had.
As for Hashirama Senju — Finn didn't know how long it had taken the First Hokage to fully integrate. Without the assistance of the Shikkotsu Forest, he believed it would have been a very long process indeed. But people of that category got there eventually. It simply cost more time than expected at the start.
Then there was Minato Namikaze, who sat outside both categories in a way Finn found oddly interesting.
Minato's talent clearly exceeded Jiraiya's. You didn't need any special eyes to see it. But he fell well short of the ceiling represented by Naruto, Hashirama, or Finn himself. Not the worst of the first category, not anywhere near the second. Somewhere in between, in the way of a student who was neither struggling nor excelling along the extremes that defined those categories.
What that meant in practice: Minato could probably learn Sage Mode faster than Jiraiya, and probably achieve it more cleanly, without the partial frog-transformation. His ratio would fill faster. But the time he could hold the state would be shorter than someone from the second category — his reserves would drain, and he'd need to stand still to replenish them. For a man whose entire genius rested on speed and continuous movement, standing still mid-fight was barely an option. The only real loss in the comparison.
Finn stood up from the stone face of the Third Hokage's carved portrait and reached for the pipe at his waist. He didn't bother looking for a flame. He drew a thread of fire-attribute chakra from his lower reserves, channeled it to the bowl, and breathed in. The tobacco caught without a spark, the ember appearing from nothing in the packed leaves. Smoke rolled out slow and even.
It was a small thing. Casual. But a year ago he hadn't been able to do it at all.
He looked out across the rooftops.
A green shape was moving along the street below, and it was moving upside down. Both hands pressed to the road surface, legs pumping in the air, the figure was sprinting through Konoha's morning foot traffic with the focused energy of someone who had never once questioned the value of what he was doing. At this stage in Konoha, only one person could possibly be doing that.
Might Guy.
"The Eight Gates...," Finn murmured softly.
He knew the broad strokes. Everyone following the war knew what Might Dai had done — a Genin who had never once passed the Chunin exams in his entire life, who had opened the seventh gate and cut down four of the Seven Ninja Swordsmen of the Hidden Mist before dying. The story was circulating in the village in hushed, slightly uncertain tones, as if people weren't sure how to hold something that fell outside every framework they had.
What Finn also knew, and what most of Konoha hadn't fully reckoned with, was that the Eight Gates were still not taken seriously at an institutional level. Not openly. No curriculum, no promotion, no instruction track. Listed as a forbidden technique, and in practice the village simply left it alone.
The reason wasn't neglect. Finn had assumed that at first, but he'd had time on this rock to think it through, and the actual reasons were more layered.
The first was the scope of commitment. To genuinely master the Eight Gates — to reach the state where you could open them in real combat — required no fewer than ten to twenty years of complete specialization in taijutsu and almost nothing else. Learnable in the sense that anyone could begin it. Practically impossible to complete, not because it was kept secret, but because the investment it demanded was incompatible with how most shinobi built their careers. You couldn't maintain a standard Jonin repertoire across multiple disciplines and also master the Eight Gates on the side. The paths were nearly mutually exclusive.
The second reason concerned talent — or rather, how invisible the relevant talent was. Looking at Might Guy, or at Might Dai before him, or at the child Rock Lee, you'd conclude at first glance that they were untalented. Lee couldn't use ninjutsu or genjutsu at all. Guy specialized in taijutsu because nothing else had captured him in the same way. Dai had been a commoner with nothing else to fall back on. But that framing missed something: their bodies were maximally suited to physical cultivation in ways that didn't become visible until the cultivation was already deep. You couldn't identify that quality early, couldn't test for it before the years of work had already been done. That made mass instruction a poor bet for the village's resources.
The third reason was the most practical, and the most damning.
The Eight Gates, at their upper levels, were uncontrollable.
That was the real institutional problem. The purpose of promoting any technique on a large scale was to create a strategic asset. Something you could deploy when you needed it and manage when you didn't. But what external control did you place on a weapon that shattered its own bindings as it activated? Danzo's tongue-sealing methods, the suppression techniques Root used on its members — those worked on genin. They would not work on someone running at the sixth or seventh gate. The surge of physical energy tearing through the body at that level would obliterate any foreign seal placed on it before the seal could do anything at all.
If you created a population of shinobi capable of opening the sixth or seventh gate, what you actually had was a population of people who could, if they chose, tear down Konoha's walls with no counter available. One grievance. One person who felt wronged by a command decision, who disagreed with how the village was being run, who had lost someone to a policy they hadn't been asked about. When there was a weapon in hand and the temptation to use it, a powerful person and a powerless person were two completely different problems.
Hence the forbidden technique designation. Hence the third Hokage having the Eight Gates sealed into the Scroll of Seals — seven of the eight entries included, the eighth a theoretical outline only, since Might Dai had never completed his study of it before the war had made its final demand on him.
The technique had never spread widely, and that was the real reason why.
Finn thought about who had actually originated it. Not Might Dai — that credit belonged to Senju Tobirama, the Second Hokage. Tobirama had discovered a fragmented scroll among the Senju family's accumulated ninjutsu records, handed down through generations from some earlier era. By the time he found it, the technique was already incomplete, portions lost to time. He'd estimated from the fragments that it was something extraordinary. But Tobirama's genius lay in ninjutsu theory and water-release technique, not in physical cultivation, and he recognized clearly that he was not the right person to develop this any further.
Out of respect for the technique and care for Konoha's future, he'd decided to find someone who was.
The person he chose was Might Dai.
Might Dai was a commoner from a background that had offered him almost nothing. No clan, no kekkei genkai, no chakra-dense lineage. He'd built his mastery of taijutsu not because it was his first love, but because it was the only path that had been genuinely available to him. That love had grown from necessity and eventually surpassed it, becoming something unalloyed. Tobirama had seen that quality and recognized it for what it was.
Might Dai had not been holding anything of particular value when that moment arrived. Then the Second Hokage — leader of the Senju, Hokage of Konoha — had walked to him and, with full solemnity, placed the fragmented Eight Gates scroll in his hands. An incomplete relic from an ancient lineage. For Might Dai the commoner, it was the most precious thing he had ever been trusted with.
He spent the next twenty years making it whole.
He completed the first seven gates. The eighth remained at the theoretical level — he understood its structure, had mapped its parameters, but had not activated it. If the Hidden Mist's swordsmen hadn't caught up with him when they did, Finn thought there was a real chance Might Dai would have closed that gap before his son grew old enough to need it.
But he'd died protecting his children. And Might Guy had grown up with the theoretical skeleton of the eighth gate in hand and, eventually, had made it functional.
Even after Might Dai's death, Konoha hadn't entirely abandoned the technique. The Third Hokage had formally included it in the Scroll of Seals — seven gates, the eighth recorded in outline only. Preserved, restricted, and left where it was.
Finn watched the green figure sprint further down the street, flip at the end of the block without breaking stride, and come back the other way.
He'd been thinking for the past few days about a potential trade.
What he had to offer was the Lightning Release Ninjutsu — specifically the Lightning Release Chakra Mode and the techniques derived from the Third Raikage's lineage. Might Guy, unlike his future student Rock Lee, was not limited entirely to taijutsu. He specialized in physical techniques, but he could still learn other ninjutsu; he simply hadn't prioritized them. If he had lightning-attribute chakra in his reserves — and Finn intended to find that out — then the Lightning Release was, in principle, something Guy could work with.
The combination of the Eight Gates at full intensity and Lightning Release amplification layered on top — just thinking about it felt like too much.
He felt a small twinge of something he might reluctantly call guilt. Guy wasn't a child. The exchange would be honest, terms stated plainly on both sides. But he genuinely respected the man. The uncomplicated way Might Guy pointed his entire being in a single direction, without apology and without self-doubt, was something Finn found himself admiring in a way that was difficult to explain. Using that as a point of entry for an acquisition felt, just slightly, like taking advantage of a quality he ought to simply honor.
He turned it over again. Then he tapped his foot lightly.
The Lightning Body Instant Technique pulled him off Hokage Rock in a pulse of crackling white. He'd incorporated elements of the shaving-step footwork into the base form over the past months, layering weight reduction and rapid cadence into the discharge. The result moved meaningfully faster than the original. Not Flying Thunder God fast — the day he'd arrived in Konoha he'd watched Minato's transit register below the threshold of his Observation Haki entirely, which meant it wasn't moving through space in any conventional sense. Space-time ninjutsu and physical movement were not the same category, and Tobirama's creation rightly held the title of fastest technique in the ninja world. Minato had taken it further still; his speed exceeded even Tobirama's, which was its own kind of unreasonable.
But for a technique that still moved through space, the Lightning Body moved fast.
He materialized against a telephone pole at the side of the road and settled his shoulder against the wood. He drew a slow pull of smoke from the pipe and watched Might Guy come toward him, still running on his hands.
"Hey, boy." Finn leaned against the pole and greeted him with a smile.
"Oh, uncle!" Might Guy pushed off with both hands, flipped clean over in the air, and landed on his feet in front of Finn with a sharp, precise impact, like it had required no thought at all.
Despite their short acquaintance, Might Guy had taken an immediate and uncomplicated liking to him. Perhaps he could sense, in some way that didn't require words, that the man in front of him had offered genuine respect — to Guy's own efforts and convictions, and to his father, who had spent an entire lifetime as a Genin and died having surpassed every Jonin who had ever looked down on him for it.
It was true that subsequent evidence had confirmed what Kakashi had said all along — this particular man leaning against the telephone pole was indeed an S-rank wanted criminal across the entire ninja world. But since no one in the village had moved to do anything about it, Might Guy didn't see any particular reason to let it change how he felt.
"Are you training?" Finn asked with a smile.
"No, warm-up." Might Guy raised a thumb and showed every one of his white teeth, entirely confident.
"Really?" Finn smiled, nodded, and then asked directly: "I'm very interested in your taijutsu and want to learn them. I came to ask you — are you willing to exchange with me?" He'd thought about it at length and decided against pretense. He would ask openly. If it worked, it worked. If it didn't, he would drop it and not think about it anymore.
That wasn't mean, was it?
After all, he hadn't lied.