The young protagonist, Yaiba is a strong-willed, easy-going but often cocky kid who was trained by his father Kenjuuro in order to become a great Samurai. After leavng the jungle and returning to Japan, he starts his adventures and the struggle against the wicked Onimaru. Apparently, Yaiba is the chosen warrior able to wield the Raijin Sword without being zapped. Trained by Miyamoto Musashi and with the help of his friends and various magical powers, he fight off the menaces that threat the Earth. As the series proceed, he slowly matures.
Air Jousting: Whenever he has to face an enemy capable of flight. Usually a courtesy of his pet vulture, Shonosuke
Everything's Better with Spinning: His Senpuken (Whirlwind Sword) consist in removing the Thunder Orb from Raijin's Sword and use the hole left to make it spin at great speed. Also the Kazaguruma (Pinwheel) attack is this.
Light 'em Up: The Supreme King Sword. Apparently the Kusanagi blade in the stinger, which can fly fast enough to reach Mars from the Earth in mere seconds.
Noodle Incident: In the epilogue he and his friends (Musashi, Kagetora and Shonosuke) ended up on Mars where they were attacked by a monstrous demon alien. Oh, and he acquired the Kusanagi sword from Okinawa too.
Sayaka is the daughter of Raizo Mine, an expert kendoka and old rival of Yaiba's father, Kenjuro. At first she sees Yaiba as an annoying brat, but their relationship improves as the series proceed and she travels with the young samurai in his journey to defeat Onimaru. She also carries the Sea-Cucumberman with her. Later in the Kaguya arc, it's revealed that she's the descendant of Taro Urashima and Princess Oto, and thus the new "Dragon Maiden", the Priestess of Ryujin and the key to unleash Kaguya's true form. In the last arc, she manage to wield the Water Demon Longsword and use its powers, and later, in order to stop Orochi's rampage, has Kaguya sealed into her body and manage to restrain her and slowly change her heart.
Heroic Sacrifice: At least three times, the first one in the fifth trial of Ryujin, the Rope of Fate, in order to show Yaiba the right one. The second time when she decided to go with Gekko in order to save Yaiba's life. Then, she accepted to have Kaguya's Ghost sealed into her body in order to force her to help Yaiba against Orochi and Onimaru.
Yaiba's pet Tiger, he's just a fat, gentle tiger and behaves more like a huge housecat than a proper tiger. He carries Yaiba and the others around on his back and sometimes helped him in his trainings. He's also smarter than Yaiba.
Miyamoto Musashi is a 400 years old man who lived as a hermit on Mount Tengu, where the Raijin Sword is kept. After witnessing Yaiba pulling the sword out of the ground he agreed to become his master and teach him the way of the sword. Despite the age he's still a powerful warrior and more than capable of kicking some ass. He also know a lot of techniques and strategies, and he can be very wise.
A Former Hakki, Gerozaemon is the first of them, and he's a Frogman. He was sent by Onimaru to kill Yaiba, but he got defeated and joined his group. Despite being a Oni, he's a really good fellow and a good chef. He often fights alongside Yaiba and the others with his trusty hatchet and his tongue. After Onimaru and Orochi's defeat he turned back into a frog.
Musashi's old rival, this master swordsman was resurrected by the Spiderman in order to become Onimaru's servant. Bent on taking revenge on Musashi, he later sees a new rival in Yaiba who manage to beat him with the power of Raijin. He the decide to follow Yaiba in order to steal his magical sword, but ends up as a stationary member of the group. He wields a magical Katana named Monohoshizao (lit. Laundry Pole), and its blade can stretch at will on command. He joins the Oda Nobunaga Tournament in the last arc but is defeated along the way by Onimaru.
One of the Seven Swordsmen revived by Lord Onimaru, Jubei is a wandering Ronin and pupil of Musashi himself. He's a man of honor and a very serious samurai, and a skilled swordmaster. However when he gets drunk he turn into a violent Wolfman who attacks anyone in sight. He's also prone to try to commit Harakiri quite often. He's last seen in the Oda Nobunaga Tournament where he fight Yaiba for one last time. Three years later, he's Walking the Earth.
Chaste Hero: When they rescue the girls from Kaguya's base they all fall for him, though he seems pretty clueless about it. In a later omake chapter he claims that attraction to women is a distraction for those who follow the way of the sword.
A mysterious hooded girl appeared in the Pyramid Arc. She saves Yaiba and heal him with her powers. Later she guides Yaiba&co inside the Pyramid (which she seems to know quite well) and help Yaiba against the various foes inside. She's actually revealed to be the Barrier Soldier, one of the four top class Soldiers, ans a Cyborg, created to lure Yaiba inside the Pyramid. However for some reason she sides with Yaiba instead of betraying him. She's blasted into pieces by the Pyramid Core's Lasers defending Yaiba.
A mysterious and very rich girl who appears in the last arc and introduce herself as Yaiba's little sister. She tells Yaiba about his "impostor" father Kenjuuro and state that he'll meet him in the Oda Nobunaga Tournament. She later follows Yaiba on Yoroi Island and witness his battles in the Tournament.
The Big Bad of the series, Onimaru was just a student and a really skilled and no-nonsense kendoka. Eventually, Yaiba manage to humiliate him in an attempt to challenge him and eventually they become bitter rivals. Obsessed with beating Yaiba, Onimaru discovers in a secret cellar of his house the Legendary Fujin Sword, and attempt to master it, turning himself into a powerful and large Oni bent on killing Yaiba and conquering the whole World. He has displayed many powers, and has attempted many plots to Take Over the World. During the Kaguya arc he was forced to join forces with Yaiba. After getting the Devil King Sword he starts his plans of destruction by tricking the Underworld people and awakening the legendary dragon Orochi but eventually is vanquished once and for all by Yaiba who cut off his horns. He was then Put on a Bus, that came back just in time to put him as Final Boss of the Oda Nobunaga Tournament.
Calling Your Attacks: Rarely, including the Fujin Ha (Wind Devil Wave), the Tornado attack and all the Devil King Sword attacks.
Charles Atlas Superpower: Even before becoming a demon, he was strong enough to crush concrete pipes with a bamboo sword. Afte Kenjuuro's training he can put all his power in a single slash, resulting in a swordstrike capable of flattening a steel armor and everything around it.
The third of Onimaru's Eight Great Oni, he's a antropomorphic spider with Kansai accent who apparently came from Osaka. It serves mainly as Onimaru's righthand man and henchman, but is quite clumsy and incompetent. He briefly sides with Yaiba during the Kaguya Arc when his master is sealed in Carbonite.
A Mad scientist with awful teeth and a penchant for creating really dangerous Stuff. He's hired by Onimaru and provdes him weapons and advice. He also repaired the Fujin Sword and built the Onimaru Cannon, a Flying Submarine and the Furai Bazooka.
The warriors from the past summoned by Onimaru in order to kill Yaiba, they include:Miyoshi Seikai, a monk and member of the Ten Sanada Braves. Fuuma Kotaro, shinobi and fifth head of the Fuuma Clan. Amakusa Shiro Tokisada, sorcerer and a christian Samurai. Ishikawa Goemon, rogue and former ninja. Yagyu Jubei, ronin and master swordsman. Musashibo Benkei, a Yamabushi (warrior priest/sorcerer) and Matsuo Basho, poet and former warrior.
Dropped a Bridge on Him: Kotaro Fuuma's departure is quite hasty and anti-climatic, considering that he went really close to actually kill Yaiba.
Dub Name Change: In the Spanish dub, only Seikai Miyoshi and Jubei keeps their whole names. Kotaro, Shiro and Benkei are reduced to Only One Name and Goemon and Basho are renamed "Rocko el Barbaro (The barbarian)" and "Chi Pan".
Dumb Muscle: Benkei again. Let's just say he's not the brightest crayon in the box.
The last group of Onimaru's servants and probably the strongest of them all. It's composed of four demons with elemental powers and magical swords. At first they're a bit of a Giant Space Flea From No Where
Elemental Rock-Paper-Scissors: Yaiba managed to beat Rain by using the wind to wash away all the water in the battlefield, but she just make more of it out of her sword. Also Sayaka tries this while wielding the Water Demon Longsword against Burner, but it's not enough.
Furthermore, Yaiba manage to escape Dark's Dark Zone by shattering it with the light of his sword. And also Plasma, whose illusions are stopped as Yaiba use the Supreme King Sword to cover the sky with dark clouds.
Fireball: Burner's main tactic consist in tossing a large number of these at his target. Or a single big one.
Flaming Hair: Burner, of course, while Rain sports a curious case of "'Watering Hair"
Flaming Sword: The Fire Demon Longsword can engulf itself in flames and burn down to ashes everything it touches, even the other swords and their wielder.
Gravity Master: Sort of. Dark's Dark Zone attack can suck inside the shadow projected by his sword everyone standing on it.
The Moon empress and evil counterpart of Ryujin. Unlike her subjects, she appears as a beautiful woman with a Playboy Bunny-like outfit and wielding a small fan. She's really powerful, and can erase mountains from existance with her Ki-blasts. Furthermore, in order to stay young and powerful she must drain the "Essence of Youth" out of young women. Her goal is to conquer Earth and rule the planet forever. It's revealed that a thousand years ago, she invaded Japan but was defeated by Ryujin and was sealed inside the body of the Dragon Maiden, and in order to return to her original form she needs the essence of Sayaka, the descendant of the Dragon Maiden. She eventually managed to absorb Sayaka's energy via a Kiss of Death and turned into her gargantuan, multiheaded true form, and after a long battle she merged with Earth bu was sealed away by Yaiba's Ultimate attack. She's awakened during the Orochi saga and is sealed in Sayaka's body, who compels her to aid Yaiba against Onimaru. She managed to stop the Leviathan's heart in order to allow Yaiba to beat Onimaru and cut his horn. After Orochi's fall, she leaves Sayaka's body, return to her spaceship and order his subject to return on the moon.
A Large Moon Rabbit who concots a plan to kill Yaiba, which include surrounding Tokyo with gigantic walls and flood the whole city until he shows up. After a quick battle with the Kid Samurai he uses the power of Gatai first on a Lobster, and later (in order to avoid Yaiba's fireblasts, with a propane Tank. Eventually he's outsmarted by our hero, tossed in space and "Fired" back to the moon. He asks Kaguya a second chance, but she simply destroys him.
One of the Moon Generals, is a thin, weird looking rabbit who serves in Kaguya Army. When Yaiba attacks Kaguya spaceship in order to save the imprisoned girls, he, Tsukikage and Shingetsu attack Yaiba. He uses Gatai on a Shark to fight him underwater, but has his ears cut off and he's blocked in shark form.
Another of the Moon Generals, and pal of Mikazuki. He's an Elder Moon Rabbit with a long beard who fights alongside Mikazuki and Tsukikage to stop Yaiba. He "merge" with a squid, but suffers the same fate of Mikazuki.
A really short and plump Moon Rabbit, he's Kaguya's Advisor. After Yaiba's raid Kaguya's Spaceship, Jubei is left behind, and Mangetsu uses his powers to Merge with Jubei and take over his body. Later he go back to Mine house, kidnap Sayaka and attempt to kill Yaiba but is discovered. Eventually Musashi manage to make him drunk and awake his Wolfman side, who chase away the Rabbit who gets captured. When Gekko storms Mine house later, he kills him by shooting him point blank with his Bazooka.
The only Black Moon Rabbit, Gekko is an insanly powerful warrior who was imprisoned for trying to overtake the Moon. Kaguya free him in order to have him fight Yaiba and kidnap Sayaka. After his first failure, he decide to violate the cell "666" and take the Devil King Sword, which uses to utterly best Yaiba. Eventually, the combined forces of Yaiba and Onimaru manage to defeat Gekko's Sword. After the Orochi Arc he appears along with Tsukikage and the other Moon People when Kaguya "de-merge" herself and return to her "human" form. In the Anime is revealed that Gekko was mistreated and bullied as a child because of his black fur, and only Tsukikage was close to him.
These are the lesser minions from the Underworld Kingdom who defend the Pyramid. Despite being the lowest class soldiers, they're still really resilient and more than a match for the young samurai. They include the Rock Soldier, the Sugi (A Japanese conifer tree) Pollen Soldier and the Snowman Soldier
Informed Ability: The Ant Soldier is said to have the hardest and strongest body, and able to pick up items several times his size. He's actually Ant-Sized too, and so said giant boulder is revealed to be a normal sized stone.
Ki Attacks: Budou can shoot purple "grapefruit-like" Ki Blasts
Mega Manning: Sort of: Mushroom Soldier can pick up and use the Raijin Sword because his masters built him with this ability. Considering that one of his makers may be Onimaru, who possessed the Fujin Sword, another demon katana, it's quite Fridge Brilliance.
These are the top fighters of the Pyramid, and really powerful. They all look like twins girls, and each of them is specialized into a particular branch of fighting.They are Ruby, the Stong Soldier, Sapphire the Skilled Soldier, Diamond the Genius Soldier and Emerald the Barrier Soldier. They can also merge together to form Jewel, the Perfect Soldier.
The Mysterious leader of the Underworld Kingdom, he's always seen sit on his throne behind a waterfall, and he's the one behind the Pyramid and hold a huge grudge against humanity, accusing them of spoiling the Earth with wars and pollution. We find out that he was misguided by Onimaru and has one of his super Warriors turned against him and his kingdom, but is saved by Yaiba. He appears later to help Yaiba and Sayaka against the Yamata no Orochi. He also looks likeKami.
Informed Ability: When he finally appears before our heroes, he stated that noone of Yaiba's group (minus Yaiba) could even hope to hurt him. Yet, in the Orochi Arc he's stopped by a Kaguya-Possessed Sayaka with ease.
Kill Them All: After Yaiba destroys Tokyo's Pyramid he reacts by sending tons of laser-shooting black pyramids all over the world.
The Super Warriors of the Uderworld Kingdom, they're two black giants with a single eye each. They're really powerful and strong, but not very smarts. eventually Onimaru reveal himself, and use the powers of the Devil King Sword to turn Gold into a Oni, and orders him to destroy the whole underground realm, but Yaiba kills him in time with the Supreme King Sword and full power.
A European Knight, and Yaiba's second opponent. Despite his noble and proud appearence, he's a slimy, dirty cheater who's not above using vile tricks to win the Tournament and 10% of the final prize which amounts to 100000 millions Yen.
Combat Pragmatist: Using an insidious sword? Check. Pretending to be wounded? Check. Disarm your opponent with a pendulum and handshackles? Check. Concealing a Zweihander in the back of your cloack? Check!
A mighty warrior whose body was powered up thanks to "microunits" which turns him in a restless, powerful fighter who feels no pain and can increase his speed and strenght as he fights. He's the champion of the Platina leader Gakuso Shirogane and fights Yaiba in an elettrified ring.
Artificial Human: Partially averted, he's fully human with "microunits" planted in his muscles.
BFS: His weapon of choice is a very large scimitar.
Sixth descendant of the legendary Shinsengumi ''Kensei'', he's a young and powerful swordsmaster. Extremely good naturated and kind, is also a fearsome opponent with an amazing skill. Wields the famed Kikuichimonji katana.
I Let You Win: After noticing that Yaiba's assaults grow stronger and stronger as he gets up and surprised by the Toujin technique, he decide to quit. Also done in order to avoid to kill Yaiba of course.
Yaiba's father and master, is a happy-go-lucky, lazy man who wanders around the world, but is well known for his skill with the sword. He rarely appears, and he's often shown to be drunk. In the last Arc, is revealed in the beginnging that he might be an impostor who killed Yaiba's true father and kidnapped him. Yaiba will eventually meet him at the Oda Nobunaga Tournament. He actually Is his true father, (his mother lied to Moroha out of despair) who abandoned his wife in order to become a master samurai. In order to test Yaiba's skills, he trains Onimaru untill the latter become as strong as himself and let him fight with Yaiba. He eventually makes peace with Yaiba's mother.
The Mighty Dragon God, he appears as an old samurai wielding a katana. He's duty is to protect the Earth from Kaguya and other evil threats. After surviving his tasks, Yaiba is allowed to take his power, the Ryujin Orb. Is also reveald that a thousand years earlier he defeated Kaguya and Gekko. After Kaguya's second defeat, he goes away with the Orb. He reappers during the Orochi Arc to stop Onimaru, and in order to protect Yaiba he's hit by Dark's Delta Zone, and he manage to drag the Darkness Demon with him as he's sent to another dimension.