Sakamoto is an amusing idea. I can imagine him turning up at the bottom riding one of the most fearsome beasts down there
I'd suggest Koro-sensei from Assassination Classroom. I mean, he'd reach the bottom in like 10 seconds...
While teaching class...
Orby doesn't predict him because well, he's too fast, bondrewd didn't even notice he was there... I suppose the light of returning essence
Could Work on stopping his regeneration, but that would assume that someone using it could keep up with him, most of the characters we've guessed can't.
Korosensei pops back up just as fast and is not human, so he isn't affected. He just randomly shows his class some weird relics and calls it a history lesson...
I'd also argue with berserker (Hercules) that he would be unaffected by the light of returning essence as his regenerating comes from either his masters mana or full death
I'm gonna throw ryuko matoi in there, post king of the hill natural elections, when her and senketsu have much of their abilities. Even with erica mendez's dub, she seems incredibly aggressive, would probably choose to fight much of the threats chasing her rather than try to slip by them.
she'll use senketsu shippu (gale) to just fly past the third layer, but I imagine the splitjaw would notice that, but it's too aggressive to turn back from something countering it with aggression, so it gets a scissor blade to the face. Senketsu covers for any point ryuko has to ascend as he doesn't suffer the hallucinations, but she does.
Getting to orby, there's actually a few things ryuko can do, the orb peircer can see what effect ryuko's and possibly senketsu's consciousness has in the abyss, but ryuko is far more reckless than most of the things that come his way, ryuko also has life fibres in her body, so she can just leap towards the orb peircer's spines and regenerate any damage, shippu could be useful and make it look like the naturals election fight against nonon, ryuko's life fibres yet again negating the bleeding curse.
That, or she just suicide jumps at the peircer's spines and goes senketsu senjin (blade) and cut off a good chunk of those spines, regardless, it'll end in sen-i-soshitsu with orby losing virtually all of his spines, or dead.
Layer 5, if she has to ascend there she depends on senketsu's senses again, as for bondrewd ryuko again is too aggressive to simply slip by him, especially when she learns the kind of stuff volume 5 reveals, how will it end?
I'm thinking top ten anime battles there
both have lots of options to fight each other, not sure which will win but with the essence of returning light, ryuko could lose a limb or two - permanently, limiting the options she has in a fight.
If she ever makes it to layers 6 and 7, her own life fibres
Yet again Would mean she isn't affected by curses that would affect someone more human
sorry for the essay, teacher!