At that critical instant, the transmigrator's earthly soul faced what he thought was one of the hardest tasks in existence, wresting control from the original Ryusei's spirit mentally while fending off instant death externally.
He had no choice but to split his focus.
The assault on Ryusei's mind slowed, a desperate fraction of his will clawing for motor control just long enough to twist the body aside.
The enemy's kunai still carved a burning line across his neck, close enough to nick a vessel, but it wasn't the beheading strike it could have been.
Ryusei's body looked corpse-like, skin pale, sweat dripping, teeth clenched.
The enemy's eyes narrowed in faint surprise at the dodge, but his second blade was already moving, this time aimed straight for the heart, arm layered with as much chakra reinforcement as he could muster.
He had seen enough: the boy was half-paralyzed, struggling to keep upright. One clean hit and it would end.
The transmigrator gritted down on Ryusei's nerves and forced the torso to twist again, just enough to make the blade miss the heart by a finger's breadth.
Pain exploded in his side, the slash tore deep into muscle, scoring a lung.
Inside, the earthly soul roared, pushing every shred of its power outward.
He had to make a trade. The crushing pressure hold he'd kept on Ryusei's spirit loosened for the first time since the genjutsu struck, and the battered soul beneath it twitched, sensing the gap.
Even half-blind in the haze, the original's will began scraping at him from the edges, fighting to stay alive now that it finally understood the danger.
It was a risk, but he didn't have a choice; without shifting that focus, the body would never move in time.
The body moved. One hand shot up, seizing the chunin's wrist mid-swing.
With a violent pull, he dragged the man inward, the other arm snapping up kunai wreathed in a blazing sheath of overcharged chakra, the kind that shredded muscle fibers and blood vessels just from being forced through them.
It was dangerous, ruinous to the body, but the limited muscle memory still accessible from Ryusei's own training guided the strike.
In less than a heartbeat, the blade tore across the chunin's neck. Blood sprayed in a hot arc, and the man's eyes went wide.
A lifetime of battle reflexes had not prepared him for dying to what looked like a half-dead opponent. He collapsed.
Ryusei's arms trembled violently, fingers locking from strain. The muscles were wrecked, tendons screaming.
He was riddled with injuries everywhere. His torso was a mess of blood and torn flesh, one lung wheezing uselessly.
And there was no time, shadows fell over him as the nearby shinobi closed in, less than a step away, weapons already rising. It was a hell-level situation.
It was only his ironclad will to live, tempered by months of isolation in that dark, hidden corner of Ryusei's mindscape, that kept the transmigrator's soul clinging on through the fractures, pain, and chaos tearing at him inside and out.
Gritting his teeth, he rolled hard against the dirt, hands moving on instinct. Smoke bombs burst at his sides, swallowing the clearing in a choking haze, while explosive tags tied to kunai thrown hissed to life near the closest shinobi.
The first shockwave sent them scattering, and in the same instant, a small brown form that had darted between the rocks earlier was also 'accidentally' caught in the edge of the blast by a runaway kunai. It was seemingly still observing the scene, hidden.
The hare's body crumpled mid-leap, its chakra flickering out like a snuffed candle.
It was a calculated caution. One less thing working against him. He was not careless like the original owner of the body.
Ryusei had a lot more shinobi gear than these underworld dwellers, and he now dumped all of it at once, so it had quite a considerable effect.
Flashes and blasts shook the outpost. Smoke filled the gaps between huts. The shouting turned to coughing. A few were knocked off their feet.
He used that moment to bolt. Every step burned, but the gap was there. That was all he needed.
Now, on the run, the new Ryusei let his body's instincts handle the movement, almost like putting it on autopilot.
All his focus pressed inward, locking back onto the original soul, forcing the devouring slash soul fusion to continue even now.
But the sound of pursuit was growing louder, their footsteps closing in.
If he'd been fully fused with this body, every step would have been agony. For now, the lack of full acclimation dulled the pain.
Blood still poured from him, though, and that wouldn't last. He rifled through the owner's memories, digging for something he could use immediately.
One technique came up like a flare. Yang Pulse Override Palm.
Deep orange light, tinged with red, burst from his less-damaged hand, the one that had caught the kunai earlier.
First, he restored enough strength in it to make it useful again.
Then he pushed the same light into his wrecked arm and then used that arm to heal both itself and the deep wound in his lung and torso at the same time.
It wasn't full healing. He just locked the wounds tight enough so they wouldn't rip open with every step. He didn't care about any aftereffects that might come later.
At the same time, his hands tingled with returning sensation, and his breathing eased just enough to stop the drowning feeling in his chest.
He didn't stop moving. He couldn't. And in the back of his mind, the pressure on the original soul never let up.
'I barely got out of there alive… and it still might end in a few minutes.'
The thought burned in his head as he tore a small pouch from his uniform, fingers fumbling for the smooth, round pill inside.
'I really underestimated how hard it is to chew through a soul from this world with just my measly Earth-born one… and harder still to steer a body that isn't mine.'
He popped the pill into his mouth and swallowed dry, the bitter tang crawling down his throat.
The pouch was one of several stuffed into the deep pockets of his standard Konoha green vest.
Military Rations Pills, not much to a jōnin or above type shinobi, but for a genin or chūnin, they could be the difference between being buried or making it back.
Top scientists in Konoha had engineered them with one goal: wringing more use out of the disposable ranks and squeezing every drop of value before they broke.
Not cheap either, but Ryusei's original hidden status meant he had plenty.
'Still… chakra isn't the main problem right now...', He thought, forcing his legs to keep their pace. Blood trickled warm under the fabric.
'It's my injuries… and this damned tug-of-war with the other soul. But even if I'm not low, I burned a huge chunk on that Yang Palm just now.'
'B-rank, defensive or not, it eats chakra alive. And with my body this wrecked, my natural recovery is garbage. I need every bit I can get for what's coming next.'
His mind tightened. He still had no idea who the hell had thrown that genjutsu through the hare… or how many more were lurking out here.
'Thankfully, I'd spent months buried inside this guy's mind without him ever noticing…'
'While he was sleeping, reading through the clutter of his memories, poking at weak spots of his soul, laying out how I'd make the perfect takeover when the chance came. I wasn't just swinging in blind back there and being a complete clown, and I got some of the things right.'
'But even now, it's like trying to drive a carriage with only half the reins and someone else's hands still on the other half.'
He was still racking his brain for the next move when his attention snapped outward.
He sensed Kanae Hyuga - she'd just taken down the last scout and, by luck or fate, was moving in the same direction as him.
He could never make it to where Okabe and Renjiro were cutting through dozens of enemies, and breaking through them toward safety was suicide. This was the opening.
'Wait… how the hell do I explain this to her?' His teeth clenched. 'The original Ryusei and her could barely stand each other. She was cold, looked down on him every time they spoke…'
Another thought stabbed in. 'What if she's part of the plan to get rid of him — of me — and finishes the job herself?'
It was messier than he wanted to admit, but he forced his jaw to lock and his legs to push harder. 'Doesn't matter. This way, I've got a better shot than if those bastards catch me now.'