The old leader of the Kouga clan, and grandfather of Gennosuke. He used to be in love with lady Ogen. Seems to be skilled at using poisoned needles. Gets impaled in the chest by Ogen.
Danjo's heir and strongest member of the Kouga ninja. He's a peace-loving idealist who's genuinally in love with Oboro and wants to put an end to years of hate and rivalry. His special power is a "Do Jutsu" (Fierce Ability) in his eyes, that allows him to send an attacker's killing intent back at him. Commits suicide after witnessing Oboro's suicide.
Driven to Suicide: After witnessing Oboro's death in his own arms he declares the Iga as winners, takes Oboro's with him and commits Seppuku in a river.
Karmic Death: Weaponized, as he inflicts one on his enemies using his Dojutsu.
A hunchback spider-looking man, he's the first Kouga Ninja shown alongside Danjo. Can spit a web-like phlegm that's stronger than glue. He's ambushed by the Iga ninja and finished off by Hotarubi.
Defiant to the End: When Hotarubi tries to force him to confess all he knows, he spits on her cheek. And he gets 'nighrmarishly stabbed for his trouble.
A fat, jolly ninja who's often seen near Gennosuke. Despite looking like a moron, he's very competent and quite smarter than he looks. His body is like a rubber balloon, making him able to squeeze through small openings. Is killed by Jingoro, who force himself down his gullet while in snail form.
Distracted by the Sexy: He tries to stop Gennosuke from accepting the invitation to the Iga village, but stops as soon as Akeginu politely asks him to come as well.
One of the more mysterious and grotesque members, he's said to be an astromancer ad a seer. He has no arm nor legs, but can fight with an extremely long tongue and a knife hidden in his troath. His scale armor allows him to crawl around really fast like a snake. He's bifurcated by Tenzen.
Knife Nut: Hidden down his esophagus, thought is called a "spear" in universe.
Meaningful Name: Jimushi means "Earth Insect". Look at him when he crawls on the ground, moving like a centipede.
Oh Crap: Sadly he didn't knew about Tenzen's resurrecting skills.
Overly Long Tongue: His only weapon. Though considering how freaking skilled he is in using it to replace his limbs.
Kisaragi Saemon
Member of the Kouga Ninja he's a short and sneaky guy whose eyes are always shut. He's Okoi's older brother. His powers allow him to transform into anyone, simulate voices and even change his size. He's eventually tricked by Tenzen and killed by the soldiers escorting the Iga ninja.
Beware the Nice Ones: Despite his docile looks, this is the same dude who slices Hotarubi's arms off and then proceeds to impale her against a tree.
Big Brother Instinct: Towards Okoi. When she became his Dead Little Sister, all bets were off in regards to him. Certainly explains the horrible way in which he killed Hotarubi, when not even a single hour had passed.
Eyes Always Shut: He opens them only when proving strong emotions.
Manipulative Bastard: Can be very sly and sneaky. Specially seen when he imitates Akeginu's voice to confuse Koushiro and allow Kagerou to give him a Kiss of Death.
Master of Disguise: He can turn into anyone at will by taking a model their face from a mud mask. It's stated that he can even change his height, but for some reasons he can't copy the nostril's hair.
A good friend of Saemon and Danjo's advisor. He's Gennosuke's maternal uncle and he taught him everything he knows, including the Dojutsu. He appears to be blind and has an excellent hearing but he can actually use the dojutsu, but only by night. Gets killed by Koshiro, since being blind he's able to work around the Doujutsu's only weakness.
Died Standing Up: Against Koshiro, driving him mad as he can't determine if his opponent is dead or not.
Handicapped Badass: The man has severe eyesight problems, though the exact source and effects vary per media. In any case, he's still not to be trifled with.
Parental Substitute: Helped raise Gennosuke after the death of his older sister aka Gennosuke's mom.
A large and massive ninja of Kouga. Always seen around Hyoma and Saemon. He's very strong and can merge with the groud and any solid surface, allowing him to move around unseen. As a child he was traumatized by his father's death and shaved his head because of that. He's impaled by Tenzen while trying to flee from him and his corpse is merged inside a wooden panel, exhibited as a warning to the Kougas.
Big Damn Heroes: First when he saves Saemon from Yashamaru. Later, when he stops Tenzen from raping Oboro by snapping his neck. (Didn't likely intend to save Oboro, but whatever).
Leeroy Jenkins: At one point he decides to leave the main group despite Gennosuke's plans and directly go for the Iga ninja.
My God, What Have I Done?: In the anime, he's horrified when he mistakenly kills the flutist father in front of everyone, including his kid. The fact that his dad's death was his own Start of Darkness doesn't help. And It Gets Worse as his shock over that is what lets Tenzen kill him.
Used to Be a Sweet Kid: Young Gyoubu, as per the anime, was a very sweet child. Then his father died...
Okoi
One of the two Kunoichi of Kouga, she's Saemon's little sister. She's a large, well muscled girl that despite her body acts more like a tomboy, but she's ready to take advatage of her large breasts if needed. She's a human-leech who can drain people's blood from her skin, causing also physical pain. She gets captured and tortured by the Iga clan and eventually is killed by Nenki while trying to escape.
Badass in Distress: The Iga clan capture her and torture her. This doesn't stop her from killing Rosai and almost doing the same to Jingoro and Nenki. If only Nenki had not been able to counterattack.
Boobs of Steel: Amongst the Kouga Ninja she's the strongest female character and also the bustiest.
Plucky Girl: She will never EVER give up on anything she wants or needs. Even when she's about to kick it, she manages to tell Saemon where's the scroll in her last words.
Stripperiffic: Again, justified as she needs to touch someone with her bare skin to suck his blood.
Kagerou
The other kunoichi of the Kouga clan. She's a feminine woman with black hair, madly in love with Gennosuke and jealous of Oboro. When she's aroused, her breath becomes a poisonous miasma. She's horrorifically raped and tortured with needles by Tenzen, which drives her into insanity.
Angst: Given her powers, this is pretty justified.
Clingy Jealous Girl: She hates Oboro and wish to kill her with her own hands. Far more accentuated in the anime, tho, where she reaches Yandere extremes.
Death by Sex: Weaponized, as she inflicts this on anyone who's fool enough to lay with her.
Go Out with a Smile: As she's about to die, Oboro looks at her and nullyfies her powers, allowing her to die close to Gennosuke's face.
The old leader of the Iga clan, she used to be in love with Danjou. Her powers are unknown but she seems to have a tamed falcon as a pet. She's the very first person to die in the manga, killed by Danjou's needles. Though not before she takes him with her.
Brutal Honesty: When informing Oboro that she's far too clumsy to be a ninja. (Though she's not as harsh in the anime.)
Ogen's granddaughter and Gennosuke's soon-to-be wife. She's a very sweet and clumsy person. She can't fight, but her eyes have the power of cancelling any ninja power or technique seen, which is considered as one of the most deadly powers in the whole series. After going throught a long series of Break the Cutie moments she kills herself in order to allow Gennosuke to win.
Spanner in the Works, as her death derails Ofuku's gambits and sends her into a Villainous Breakdown. And we're not mentioning how she was vital into killing none other than Tenzen a short while before.
The first Iga ninja shown along with Ogen. He's a pretty boy who can use the hair of deceased women as deadly strings. He's Hotarubi's boyfriend. He's killed by Gyobu.
Nice Guy: He's one of the few ninjas who doesn't really enjoy fighting and prefers to live peacefully with Hotarubi.
Razor Floss: Made from the hair of deceased women bathed in a special oil.
Traumatic Haircut: During the battle against Shogen, his long black hair gets hacked off.
Yakushiji Tenzen
A very high-ranked Iga ninja serving Ogen, he's one of the strongest members, and surely one of the most evil characters in the manga, and that's saying something. He's the mastemind behing the Iga-Kouga war. Has an unhealthy attraction for Oboro. Thanks to a parasitic twin living in his body he can come Back from the Dead at will. Is eventually beheaded by Gennosuke and destroyed when Oboro use her Anti-Magic on the parasite twin while at work, thus nullifying his powers.
Back from the Dead: He was born with a parasitic twin inside his body. Said twin is normally seen as a small bulge on his ear. If Tenzen's killed, the twin reach the wound and "eat it", allowing Tenzen to raise from the dead.
Big Bad: Surely he's the most suitable character for the job.
Body Horror: How his resurrection works. This gets disgustingly bad the last time, when you see the parasite using Tenzen's sliced neck as a mouth to speak.
The Chessmaster: He's the mastermind behind the new conflict.
Rubber Man: Can stretch his limbs and neck. Josuke even calls him a "Rubber monster".
Mino Nenki
An odd-looking shinobi with very long and messy hair, huge eyebrows and long nose hairs. He can animate and control all the hairs of his body and can use a long staff. Hyoma use his dojutsu on him, causing him to breaking all his own bones.
Bifurcated Weapon: His staff can actually become an oversized nunchaku.
Big Ol' Eyebrows: Gennosuke and Danjou's are nothing compared to this guy.
Jerk with a Heart of Gold: He's genuinely affectionate to Oboro, and while everyone shuns her away and think she's useless, he only says she's Just a Kid.
A skilled warrior and shinobi, he's very protective towards Oboro and possibly in love with her. He obeys Tenzen's orders, but he's not as evil as him. Can fight with two kama sickles and use his breath to form a deadly Razor Wind attack. Halfway through the manga he's blinded by Gennosuke, who sent back his wind at him, but learns how to fight while blind. He's eventually poisoned to death by Kagero, who he thought was Akeginu thanks to Saemon mimicking her voice to distract him.
Disability Superpower: After being blinded he gains a better sense of hearing, allowing him to fight and kill Hyoma as now he's immune to his gaze.
Dual Wielding: Sickles. He can even throw them with deadly precision.
Even Evil Has Standards: He's clearly not okay with the idea of Tenzen forcing himself on a defenseless Oboro. In fact, as this happens, Koushiro is outside the room and clearly forcing himself to not intervene, torn between his loyalty to the one who raised him and his own love for his lady-of-liege.
Eye Scream: Gennosuke's gaze force him to damage his own eyes with his Razor Wind.
Hidden Depths: He has a soft spot for kids and is an excellent woodcarver.
A slug man from Iga who can melt his body with salt in order to lay ambushes and move faster. However too much salt reduce him to a pitiful squealing worm. Water can return him to normal. He's deeply afraid of the ocean for obvious reasons. He's killed by Gyobu who tosses him in the sea, causing him to melt before Akeginu can help him.
Why Did It Have to Be Snakes?: He's scared shitless of the sea. Justified as, due to the salt in it, his body would melt upon prolonged contact. And that's what happens to him.
Akeginu
Iga kunoichi, she's a beautiful woman who serves as Oboro's maid and actually cares for her plea. She can expel blood from her skin and use it in battle along with daggers and shortswords. She's in love with Koshiro. She's eventually tricked and captured by Saemon, and stabbed in the heart by Kagero.
Kunoichi from the Iga clan and Yashamaru's lover. She can summon and control insects and snakes to do her bidding. She's only sweet and gentle with Yashamaru, and tends to be violent and rude to anyone else. She's maimed and killed in battle by Saemon.
Death Glare: Her default expression around anyone who's not Yashamaru.
Though even he gets one when he jokes about Oboro's cuteness.
Ensemble Darkhorse: Both she and Yashamaru fall under this trope, and they are the most popular Basilisk characters ever. Heck, not even Gennosuke and Oboro are that much loved!
Friend to All Living Things: She can use her powers to summon butterflies against her enemies, though she also has a pet snake and in the anime she can control many kinds of bugs.
Tokugawa Ieyasu: The elderly former Shogun, who appears to be suffering from some sort of throat cancer as evidenced by the bulbous growth beneath his chin. Although retired, he still possesses enough influence within the government to revoke the Hattori truce in order to resolve the succession dispute. Historically, Ieyasu is regarded as an effective but extremely heartless ruler: Basilisk maintains this image of him as he clearly views both Koga and Iga as expendable in the face of ensuring political stability and his family's grip on power, thus forcing them to fight to the death.
Hattori Hanzou the First (Masanari): The head of a prominent ninja family from Iga Province who would later become chief of the Shogun's intelligence. In the anime, he helped the people of Tsubagakure escape Nobunaga's attack. The peace treaty between Iga Tsubagakure and Kouga Manjidani was originally implemented by him.
Hattori Hanzou the Fourth (Masahiro): The third son of Hattori Hanzo and the current leader of the Shogun's intelligence. Although he dislikes the idea of turning Koga and Iga loose, his loyalty to Ieyasu compels him to nullify his father's anti-war pact for the sake of avoiding civil war among the other Shogunate retainers. He was among the audience that witnessed the duel between Yashamaru and Shogen at Sunpu Castle and would later witness the duel between Oboro and Gennosuke alongside his adopted son Kyohachiro and Lady Ofuku. Although his demeanor can be considered cold and non-chalant, he was deeply moved by the second duel and enacts a new peace treaty in which the spoils promised to the winner were evenly distributed between both clans. He also recoves the battle scroll from Ieyasu and secures it in a hidden alcove of his Japanese-style Big Fancy House, so that the memory of the 20 chosen ninja would not be completely forgotten.
Hattori Kyouhachirou: The nephew and adopted son of Hattori Hanzo the 4th (his birth father was Hattori Hanzo the 2nd). Kyohachiro was charged by Hanzo to monitor the duel between Koga and Iga and then report the results to him and Lord Ieyasu.His role is greatly expanded in the anime: in the manga he doesn't appear until the fourth volume (when he reports to his father that Lady Ofuku had departed in an attempt to sway victory in the Iga's favor), whereas the TV series has him appearing somewhat earlier and getting along more or less well with Oboro.
Nankoubou Tenkai: A Tendai Buddhist monk and political adviser for the Shogunate, he suggested to Ieyasu that since the Tokugawas are a military family, the succession dispute should be settled though some sort of organized duel between ninja instead of valued samurai. As the duel between the Koga and Iga rages on, Ieyasu sends him into the inner castle to keep the peace between Ofuku and Oeyu. He later returns in Basilisk's sequel series, The Yagyu Ninja Scrolls, where he takes on a more saintly role. He is the twin brother of Ashina Dohaku, who serves as the main villain in the second half of The Yagyu Ninja Scrolls.
Yagyuu Munenori: A Kenjutsu instructor of the Yagyū Shinkage-ryū school, of whom the Tokugawa Shogunate was a loyal patron. He was among the audience that witnessed Yashamaru and Kazamachi's duel at Sunpu and follows the war alongside Ieyasu. Because of their barely reined hostility to each other and the awesome power of their techniques, he views the ninjas of Kouga and Iga as being more akin to demons than humans.
Ofuku aka Lady Kasuga: The godmother of Takechiyo and leader of the faction supporting his claim to the Shogunate. A cold and heartless woman who murdered her husband's mistress and illegitimate child when they're brought into the household, Ofuku's only redeeming grace is her devotion to her protege Takechiyo whom see considers a surrogate son, at one point even risking her life to save his when the Kunichiyo faction poisoned him., Ofuku attempts to personally intervene despite orders from Ieyasu to the contrary, taking the side of the Iga and forcing Oboro into many problems. After witnessing Oboro's suicide, Ofuku rashly orders her samurai to asassinate Gennosuke, only to witness them die at the hands of his dojutsu. Although Gennosuke decided to spare her life, Ofuku is mentally crushed after the Iga's apparent loss; as punishment for her scheming, Hattori Hanzo decides to keep her in the dark regarding how Gennosuke abdicated victory.
Takechiyo: Ieyasu's eldest surviving grandson, represented by the Iga. His slow witted nature is the basis of the succession dispute. He will grow into Tokugawa Iemitsu.
Kunichiyo: Ieyasu's second grandson, represented by the Kouga. Although the younger of the two brothers, Kunichiyo's intelligence and cleverness has caused many within the government to view him as more deserving of the Shogunate over his elder sibling. He will grow into Tokugawa Tadanaga.
