It, worked? Jestar had been banking on this working or else, and as he went through the steps he found himself almost happy. Then, unwittingly, he had executed both a great play and a great mistake at the same time. He took his heart away, causing him great pain and releasing him from the genjutsu.
Whoops.
Jestar would have no time to articulate such a thing, however, because in the follow-up as Jestar returned to his own form was a light so blinding and so great that one would think that they had stared into the rays of the sun for several minutes. Forced to his senses and the realization that his plan had been flawed, Jestar's only chance at this point was to attempt to flee to the shadow dimension.
But, how would this attempt play out? After all, Athos' sword of revealing light clearly removed the shadows from the surroundings, he could not just merge into them. Not that merging into them would be optimal, but still. Well, as Athos had correctly guessed in assuming that the light alone would not prevent him from escaping to the shadow dimension, the man had likely not assumed why, the reason being the very same one that took his heart away. The presence of shadows inside of the body.
What, you say? How can there be shadows inside of the body? Well, if you have ever looked into a dog's mouth, or your own mouth for that matter, you will notice that the light extends only to a certain point, before anything further than a certain point is shrouded in shade. This shade, this shadow, is what makes Pop's shadow imitation curse so difficult to break (unless upon someone trying to use that you literally disconnected their mind and body via the shadow connection, but so much for that surprise now) as truly eliminating all shadow in the body was impossible using conventional methods, and still difficult using the supernatural ones that ninja were typically afforded.
If Jestar indeed would not be prevented from entering the shadow dimension, then surely Oken's light only affected the shadows outside of objects and not within them, at least on this stage? Poetic licence aside for a moment, what good would it do for Jestar to still have access to the shadows inside of his body? Wouldn't he still be cut in half no matter how he slices it?
Well, as Athos had hinted at, at this point, it was not a matter of who died and who lived, but a matter of who died first and who lived last; Jestar was at an advantage in that up until Athos decided that bisecting and setting him on fire was the best way to go. The French of the 100 years war would only disapprove because Jestar was a man and not a woman, and not thier personal war hero against the English. Jestar was an ANBU, a shadow in the night, not a heroine defying the gender steroetypes of her day. I mean, look where that got her! At least Jestar would not be burned by his people!
Athos is a Nara? Oh, well, err, he is also an Uzumaki, so there is like, just enough... Jestar's a Hyuuga so what does that have to do with anything? Okay so MAYBE he is technically also getting burned by one his own people. Fine, just ruin a good analogy while youre at it. Back to the fight then.
Oh if only he had used an ordinary blade, how simple it would be to have his internal shadows have the blade slip right through him! But it was no ordinary cutting object, it was, effectively, the Borderlands version of the lightsaber, complete with incendiary damage for extra damage against Warriors and giant toothed orifices alike. Handsome Jack would probably go after Athos for his banditry though.
So while using shadow migration Jestar could save, say, his head, and his chest cavity from both the laser and the fire damage, he would still be missing a large portion of his midsection and his legs, that much left behind and burning to a crisp. Time constraints you see, prioritizing what's important, having children if some horny maiden were to come by and be into necrophilia not being high on the list; again, going back to the original premise of this stage of the fight, it was not who lived and who died, but who died the quickest that would separate winner and loser.
Athos had cut Jestar's advantage to size, roughly in half to be logical here. The absolute vitals, the heart, the lungs, the brain, they remained connected and intact, for the most part. As a diagram of the body would generally show, the heart and lungs are not directly in front of or on top of the stomach, so regardless of Athos' idea of "stomach" being that of the superficial belly or the organ itself, the slash itself would not also cut through his heart and lungs.
Shadow Migration
But where would this leave Jestar?
Assuming he succeeded with his, admittedly, desperate plan, then Jestar would appear in the shadow dimension with a portion of his midsection gone Darth Maul style; at least he would not have to worry about extended visits to the porcelain throne, nor about having to pay child support, because there went any aspirations for that too.
With half his body sacrificed, then, Jestar would appear in the shadow dimension, with his howl of pain the last thing to be heard before his retreat, presuming he was successful at his retreat attempt. Suspended there, his eyesight gone and only the sense of eternal shadow around him, the young man would try to fight death off with a shadowy stick, using the all surrounding shadow to keep his remaining contents (blood and all that) from spilling out like a horror victim in a not so typical jumpscare movie. A few meters in front of him would be Athos' heart, seemingly frozen in whatever beat it had been in when it had been filched.
So, what now, the question would have came up again. If that didnt kill him then what would? Not us he might would say, but he would need to know for sure. This is all presuming he survived.
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Of course, if Jestar's attempt failed, for reasons being the most likely of his shadow imitation not working or something more nefarious, I have also written out his death as well. I mean, what kind of fight is without its ending post eh? I am not that sort of poet, no, I am the sort that gives finality dignity to his characters!
If his plan were to fail, then as Athos predicted, Jestar would be severed and emit a large amount of static eletricity. Even his sword cut in two, you would think this a pointless thing, to charge up his Blade of Thunder. The sparks would emit, but they would be hardly visible what with the Oken in play, and would only be audible. As Jestar's dismembered top would fall towards the ground, the sparks would become more and more aggressive until his top hit the ground, still burning.
A large boom would emit from the sword, akin to a roar, that might would startle Athos, but mostly served to give a resounding final canon's blast as Jestar's life faded into the nethers. Shinigami would scoff at Jestar's quick end, but Jestar would reiterate that a double power move + poison = death even for the best of the fighters of the realm. The sparks faded, the sword no longer gleaming with life; the burning corpse lay motionless, convulsing one last time as if one last futile effort to make a handsign, before finally laying to rest, for good. Now for Athos to hobble on home and maybe die, well, that would call it a draw, but there was no victory for Jestar in even that scenario.
In the afterlife, meanwhile, Jestar would find himself in a famaliar scene; the Graveyard. Picking up his ethereal form from his supposed location, the red eyes and snarling growls of monsters reached his ghostly ears.
"Welp, I'm not going to get favor just standing around here!" And so, Jestar would float from his entry point to the Graveyard and set out to restrain rebellious and monstrous souls, all in the effort of winning favor from the lord of death, Shinigami, so as to have what remained of his body stitched back up by the black magic of that demon. It was as if he had gone through this task a dozen times before, and knew he might would have to go through it a dozen times more; it was a part of living life in the realm, dying, and he was not one to shirk. He missed being able to haunt his foes, but that worked both ways, and there were others who haunted far more deviously than Jestar could even imagine; he was a genjutsu user, so of course he has a very vivid imagination on his own!
The details of all of that, however, are a different story entirely, and may not even need to be told if Jestar succeeds with his shadow migration escape attempt.