Among all action anime series out there, one of the most popular and well known is Tite Kubo's Bleach. In this franchise, Soul Reapers are humanoid spirits who wield magical swords and spells, and they exorcise evil spirits on the field of battle. One of them is Captain Byakuya Kuchiki.
Captain Kuchiki is an aristocratic and confident man with many kido spells at his disposal, deep knowledge of Soul Reaper lore, and a zanpakuto that can form swarms of petal-like blades that slice opponents to bits. With his shikai, and his bankai (Senbonzakura Kageyoshi), let's see who he can take on in the anime world, and which characters would squash him. Captain Kuchiki is in for the fight of his life.
10 Can Defeat: Katsuki Bakugo (My Hero Academia)
Granted, this would be a pretty tough match even for an experienced Soul Reaper for Byakuya Kuchiki, but we're sure that the Captian could take out King Explosion Murder. Bakugo boasts sharp combat intuition and powerful explosives, and some killing intent, too.
But Byakuya is faster, and he can evade whatever Bakugo might throw at him. And while Bakugo's fierce explosions could blow away Senbonzakura's petals and some kido attacks, Byakuya could feint with an attack, then performed a flash step to get behind his opponent. Bakugo would be too slow to block an attack from behind, and from there, Byakuya could finish him off in all kinds of ways.
9 Can't Defeat: Lord Boros (One-Punch Man)
This is the most powerful villain to appear in the first season of One-Punch Man. He is an alien overlord with godlike power, and he can take punches from Saitama... and get back up. Now that's a villain.
In fact, it's clear that only the likes of Saitama can take him on, and Saitama is overpowered to the point of being a parody of superhero fiction. Byakuya can't match that, and he can't match Boros' capacity for healing and defense. At best, Byakuya would retreat with his life.
8 Can Defeat: Scar (Fullmetal Alchemist: Brotherhood)
The hulking Scar is an Ishvalan monk turned vengeful warrior, and he uses his incredible strength and endurance to punish State Alchemists and outlast them in battle. And of course, he's got destructive alchemy via his arm tattoo.
Scar's destructive alchemy and combat skills will buy him time against Byakuya, but he's doomed to lose. Byakuya's speed is superior, and he has more ranged options, from bankai to Byakurai (lightning kido) to who knows what else. Most importantly, Byakuya can use the kido known as Riku Jokoro to lock Scar in place. Then, taking Scar out would be a breeze.
7 Can't Defeat: Sasuke Uchiha (Naruto)
Sasuke is a serious powerhouse in his own franchise, and from the start, he craved power, more power, and even more power beyond that. He wields the Sharingan like a pro, and he upgraded it to unbelievable new heights. Beware those eyes.
On top of the Mangekyo Sharingan and its many powers, Sasuke boasts top-tier speed, power, jutsu, and combat intuition, allowing him to craft all kinds of plans. Byakuya could keep up with Sasuke's speed, but not even bankai can handle the Susano'o, Tsukuyomi, Chidori, and the other techniques in Sasuke's bag of tricks.
6 Can Defeat: Joseph Joestar (JoJo's Bizarre Adventure)
In a battle of strength vs strength, Joseph Joestar proved himself a serious contender when he took on the fearsome Pillar Men and bested them, one by one. Not even the god-form Kars could survive Joseph's tricks. Later in life, Joseph acquired his stand, Hermit Purple, too.
He would last longer than expected against Byakuya Kuchiki, but not even his acrobatic ways and Hamon would see him through to victory. Byakuya is too fast, and his kido would strike Joseph from unexpected angles. And like Scar, Joseph would be helpless once Riku Jokoro locked him in place.
5 Can't Defeat: Sho Kusakabe (Fire Force)
Don't be fooled by his young age. Sho Kusakabe is a knight of the order of the ashen flame, and he has proven himself as the toughest villain yet for the firefighters. What can he do? He can control the universe's heat and lower it to zero... and thus stop time itself.
Unless Byakuya lands a lucky blow against Sho early in their duel, it's "gg" once Sho activates that incredible power. Byakuya is fast, but if he's frozen in time, he's a sitting duck, and Sho would carve him up into bits.
4 Can Defeat: Ken Kaneki (Tokyo Ghoul)
This is another close one. After all, Ken is tough, fast, and ruthless once he survived being tortured by the Aogiri Tree and fully accepting his ghoul status. His kagune grows stronger and stronger, and he's more creative than most ghouls.
So, he could push Byakuya pretty far, but not quite all the way. Once again, Byakuya's flash steps would allow him to survive the worst his opponent can dish out, and his bankai will meet Ken's kagune in a contest of strength vs strength. If need be, Byakuya can activate Shukei: Hakuteiken, and manifest a dazzling white sword and wings to finish off his foe. Not even Ken's tough kagune could block an attack like that.
3 Can't Defeat: Milim (That Time I Got Reincarnated As A Slime)
Don't be fooled by her appearance, though Byakuya might be. She is a demon lord, and easily one of the most powerful beings in the entire franchise so far. In fact, Rimuru Tempest, for all his power, had a tough time in their duel, and he opted to distract her with food and end the fight in a draw.
Byakuya would probably take Milim too lightly at first, and he would pay for it. Her attacks are devastating even if she's taking things casually, and once she unleashes her full strength, Byakuya would be lucky to escape at all.
2 Can Defeat: Ranma Saotome (Ranma 1/2)
This is a character from an older series by famed manga author Rumiko Takahashi. For those not familiar with him, Ranma is a quick, tough, and creative martial artist who has a resourceful streak on top of his powerful techniques. He's not above playing dirty, either.
This served him well against many opponents, but he's met his match this time. He is fast, but the flash step is faster still, and Byakuya would score some early blows against Ranma. Not even Ranma's most powerful technique, a tornado made of mingled hot and cold battle auras, could keep Byakuya back for long.
1 Can't Defeat: Goku (Dragon Ball Franchise)
Goku is the Superman of the anime world: a tough, benevolent being who arrived from outer space and swears himself humanity's protector. Throughout the series, he becomes ever stronger and learns more and more techniques. By now, it takes a truly incredible being to push him, let alone kill him.
Byakuya is fast, but so is Goku, whose speed contrasts with that bodybuilder physique of his. As for ranged techniques, Goku has plenty of those too, and hie has an indomitable fighting spirit and can endure long past the point where other warriors would give up. Whatever Byakuya did to him, Goku would survive it and return the favor with interest.