Voiced by: Tomokazu Sugita / Patrick Seitz

The main character: a rebel outlaw with a bad attitude, a short temper, and an axe to grind with the Librarium, the international government. After destroying a branch of the Library and having a colossal bounty put on his head, he sets out for the city of Kagutsuchi in order to destroy the last "Cauldron" and prevent the resurrection of the Black Beast. His Drive ability, Soul Eater, drains his opponent's health, adding it to his own. He can also activate the Azure Grimoire in his right arm to strengthen this ability, at the expense of his own health.

He's Jin Kisaragi's older brother. Their rivalry stems from when they were younger, when Jin used to bully their sickly sister Saya. One day, Ragna noticed that the church the three of them lived in was set on fire. When he entered, he was ambushed by Terumi (disguised as Jin), who cut his arm off, and was left to die inside the burning building. A combination of the trauma and the Azure being implanted in him caused one of his eyes to turn red and his hair to turn white. He was then taken in and trained by his master Jubei, who gave him his signature coat and sword, as well as the title of "Bloodedge". The Azure Grimoire that he possesses is actually only half of a fake, the other half belonging to Nu-13. His Astral Finish turns his blade into a scythe as he proceeds to smack his opponent in the face with it, then he transforms into... something, and unleashes a final strike that completely erases the opponent from existence.

In Calamity Trigger's true ending, he is saved by Noel from falling into the cauldron and becoming the Black Beast. As such, Nu dies and all is well... until Terumi shows up and observes Noel surviving as a possibility of the Continuum Shift. After a brief scuffle, Noel tags along with Ragna for Continuum Shift, but then Ragna tells her off and sets out on his own to kill Terumi. They fight, but it is revealed that Noel is already being tempered by the cauldron, and he is unable to stop her transformation into Mu -12-.

In Continuum Shift's true ending, after witnessing Noel's transformation he fights Terumi until he can no longer stand. Just as Terumi is about to deliver the killing blow, Lambda, now with the soul of Nu awakened from her slumber, sacrifices herself and her Idea Engine to save him and grant him enough strength to counteract Terumi's Azure Grimoire. He heads to the cauldron and deals with Noel, sacrificing his Azure Drimoire arm in order to undo the tempering that turned her into Mu, but this single moment averts the attention of Takamagahara for just enough time that Terumi can hack the system and shut them down. The Imperator appears before him and Ragna is shocked to see that the Imperator is a beautiful woman who looks just like his sister Saya. Kokonoe builds him a mechanical arm out of Lambda's remnants, and he heads off with Taokaka to investigate Ikaruga, leading to the events of Chronophantasma.

In Chronophantasma, his Overdrive is Blood Kain Idea, a former super move of his that grants him extra strength on his attacks and life-draining abilities. It used to drain his own life as well, but this is no longer the case in Chronophantasma. It also doubles the now-reduced damage of his Devoured by Darkness super.

Voiced by: Tetsuya Kakihara / David Vincent

The Rival. Major Jin Kisaragi is one of the elite commanding officers of the NOL. Known as the Hero of the Ikaruga War, Jin is aloof, cold, arrogant, borderline sociopathic, and teeters on the edge of insanity, with a disturbing and almost incestuous fixation upon his brother. Despite all this, he genuinely earned his status, and is respected among the NOL's ranks, even though his own opinion of the organization is dubious at best. Jin also has an irrational hatred for his subordinate, Noel Vermillion. When he heard Ragna had been sighted in Kagutsuchi, he actively disobeys the Library's orders and hunts him down by himself. His Drive, Reitou (Frost Bite), freezes his opponents.

Ragna got fed up with his especially needy attitude as a kid, and when Ragna ignored him in favor of Saya (whom Noel resembles, which is why he hates her), Jin's slow path to insanity began. He apparently began having visions of the future, which may or may not have been induced by Terumi or Yukianesa, and this eventually caused him to burn down the church where his family lived after it was revealed to him that Ragna was technically responsible for the world's current state. He watched with satisfaction as Terumi cut off Ragna's arm and left him to die. Terumi then ran off with Saya and Jin, wiped Jin's memory of the incident, and Jin never saw Saya again. He was later adopted into the noble Kisaragi house, joined the academy, and quickly rose up the ranks. His sword, Mucro Algesco: Yukianesa, is a katana with a blade made of pure ice; it's one of the Nox Nyctores, an Evil Weapon that both rekindles his lost memories and inspires homicidal fury around Ragna and Noel. His Astral Finish involves him firing a small but fast wave of ice on the ground that is unblockable. If it connects, the opponent is frozen along with the background, then shattered.

After the events of Calamity Trigger's true ending, he wakes up on an NOL airship, which is a trap set by Hazama. After escaping, he sets out to find Ragna again, but in his haste to confront Ragna he forgets exactly how wounded he is. In his canon path in Continuum Shift, he has an encounter with Jubei, whom he doesn't recognize at first and whose advice he brushes off. Rachel intervenes and teleports Jin to her castle to "play with him", and then has Valkenhayn perform a treatment that restores him to peak physical condition for a while, but after it wears off Jin will be in much greater pain than he had been before. He is immediately teleported to Ragna's location and fights him, but realizes that Yukianesa doesn't respond to him. Ragna reveals that the sword has been using Jin and preying on his emotions, increasing his obsession with Ragna and hindering his will to the point where he can no longer utilize his ice powers of his own volition. Jin tries desperately to make his sword respond, but this fails and after trying to chase after Ragna, he is stopped by Tsubaki, who has been given orders to kill him by Hazama. Tsubaki pleads with Jin to return, but he refuses and tells her that he despises the way the Librarium works. Their argument continues until Hazama intervenes and reveals that he had planted a piece of Ouroboros into Tsubaki, which brainwashes her into revealing her hidden emotions of jealousy for Noel. After trying to desperately plead with Jin to come back a final time and being refused, Tsubaki undergoes a transformation and decides to take him in by force, but Jin's newfound resolve to protect his childhood friend allows him to focus his mind and summon Yukianesa's full power. Jin defeats her, but Tsubaki is teleported away by Phantom before he can act. He now understands what Jubei meant, and after having a talk with him heads down into the Cauldron, where he encounters Hakumen and Mu. He fights Mu and holds his own for a while, but is eventually defeated and can do nothing but watch the events that transpire. He is then taken in by Jubei to teach him how to further utilize his Power of Order.

In Chronophantasma, his Overdrive is Reishi (Frost End), which enhances his freezing abilities by causing every attack involving his sword Yukianesa to re-freeze the opponent.

Voiced by: Kanako Kondou / Cristina Valenzuela, Laura Bailey (CS2, Arcade Mode)

A hapless Lieutenant in the NOL serving under Jin Kisaragi. She trained at the academy along with Jin, Tsubaki Yayoi, Makoto Nanaya, and Carl Clover. When Jin rushes off to hunt down Ragna without permission, Noel is assigned to stop him and bring him back to The Library. The guns she wields are the Arcus Diabolus: Bolverk, and are also a Nox Nyctores. Her drive ability, Chain Revolver, lets her perform a multitude of chain combos. She suffers from amnesia. Her Astral Finish has her creating a magical seal around her opponent and shooting them repeatedly with her guns. She then detonates the seal from within by clashing the butts of the guns together.

The Material Collection reveals that she was a war orphan adopted by the noble Vermillion family. When the Vermillion family were at risk from losing their status, Noel made the decision to join the NOL in exchange for ensuring the future of her ailing father and mother. The one condition imposed by her parents was that she had to apply for non-combatant work, but after breaking all existing records for ars magus aptitude (the most important condition for Academy admittance) she was placed into a combatant program against her will. Despite her average grades, after graduation she was placed as secretary to the newly promoted "Hero of Ikaruga", although her actual job is to spy on Jin and kill him if necessary.

Throughout the story of Calamity Trigger, it is revealed that Noel is the "Eye of the Azure". She is actually the Murakumo unit Mu -12-, whose memories had been lost due to the attack on Ibukido by the NOL's Nox Nyctores Take-Mikazuchi. Noel is special because she has managed to inherit the powers of the Boundary, and is the only one who can locate the Master Sankishin Unit: Amaterasu. In the end, it is revealed that the entire story of Calamity Trigger revolves around her existence. Or, rather, it hinges on her not dying during a specific time loop so that Terumi can use her to acknowledge his existence and awaken her power, which happens in the True Ending.

In Continuum Shift, she goes to visit Jin in the hospital, but finds that he's gone AWOL and decides to pursue him. She's unaware that her old friend Tsubaki has been given orders by Terumi to assassinate her. Canonically, after defeating Tsubaki, she finds out that Hazama is behind her order of assassination, and remembers his true self as revealed in Calamity Trigger. When Norl confronts Hazama, her efforts in fighting him prove to be pointless, and Hazama shatters her emotional stability by showing her the horrors that the Black Beast inflicted upon humanity. Desperately pleading for him to stop confirming her doubts that she isn't human, Hazama cruelly tells her how the Murakumos are related to the Black Beast. This single act pushes her over the edge, and ends up destroying her Nox Nyctores, which were designed as limiters to prevent her from reverting to her original state. With Bolverk gone, Noel is successfully tempered into becoming Mu -12-. She is eventually restored to her original state by Ragna, and is last seen headed with Tager and Makoto to a safe haven designated by Kokonoe. Unbeknownst to them, Hazama already knows of this and has sent Tsubaki to follow them.

In Chronophantasma, she has a completely new outfit which discards her recognizable beret. Her Overdrive is Chain Quasar, which increases the speed of her Drive attacks.

Her Astral has also been modified. It is now a Counter Attack, and the animations where she shoots the opponent are done in an anime-style sequence as she creates a different seal from her old one. Otherwise, it is the same as before.

She eventually allows herself to be transformed back into Mu -12- by Rachel in order to save Tsubaki.

Voiced by: Kana Ueda / Mela Lee, Laura Bailey (CS2, Arcade Mode)

Vampiric Badass Gothic Lolita. Rachel is the rightful heir to the Alucard house. She hates being bored, so she heads out to the real world with her familiars Nago and Gii in tow to view the current state of events. She's also Ragna's Stalker with a Crush, although it's more out of a mix of concern and boredom than actual love. Her Drive ability, Silpheed, allows her to control the wind and change the trajectory of her movements.

It's stated in her ending that she hates her vampiric impulses, but had no choice in using them. By doing so, she ended up biting a young boy with jade-colored eyes, Ragna. She also seems to care for him and the other characters, in a thoroughly backwards fashion. She also knows about the instabilities in the space time continuum, which caused her boredom in the first place, and is attempting to Set Right What Once Went Wrong. Her Astral Finish lifts the opponent above a large crucifix as a thunderbolt strikes them dead.

In the True Ending of Calamity Trigger, when Take-Mikazuchi fires on Kagutsuchi, she abandons her role as an observer and activates her Sankishin: the Tsukuyomi Unit, which is a massive energy shield that can block anything that comes its way. She returns only to find that Terumi has succeeded in making Noel his Observer, and warns Ragna not to face him, stating that there is a "reason" that Ragna cannot defeat him at the moment, but Rachel herself only had suspicions at the time.

In Continuum Shift she is summoned by Takamagahara to answer for directly intervening with the time loops, and resigns from her position as an Observer. She then releases Hakumen from his imprisonment by Kokonoe and both of them work together to find Terumi. When Rachel does encounter him and learns that his plan is to use Noel to locate the Amaterasu Unit, she is lured into a trap created by Phantom, Terumi's mysterious assistant. She endures a taunting session from the Imperator, Relius, and Terumi before being sealed completely. Rachel is saved by Ragna in the True Ending, and is last seen speaking with Hakumen, who states that she is "too soft" for an Observer and breaks their connection.

In Chronophantasma, her Overdrive is Elfreed, which increases the recovery rate of her Silpheed gauge.

Voiced by: Chiwa Saitou / Philece Sampler

The resident Cloud Cuckoo Lander. Tao is a member of a tribe of cat-people living in a small village underneath Kagutsuchi, and is next in line to become the village's protector. To that end, she is training to become a vigilante. Unfortunately...she's incredibly dim and doesn't even realize that the person she's been travelling with (Ragna) is the most wanted criminal in the world. Her species are actually genetically-engineered clones of Jubei, the original Grimalkin. Can be bribed to do ANYTHING if food is involved, and is good friends with Litchi Faye-Ling, whom she also considers as a teacher.

Her Drive ability, Dancing Edge, lets her perform more confusing maneuvers to attack. Her Astral Finish involves her bouncing off of the walls while slashing her opponent, then performing a drill uppercut, which misses due to Jubei coming in from the left-field and being a sneaky Bad Ass.

Her Calamity Trigger Arcade and Story Mode may as well be called, "ADHD Quest". In Continuum Shift, on the other hand, she's out for a quest to get stronger. After a chance encounter with Hazama, she is beaten to unconsciousness, but is saved by Jubei before he can deal the finishing blow. In her canon ending, Tao is told by the Kaka Elder that in order to protect her village and those dear to her, she must first learn to protect others. Thus, the Elder tells Tao to go forth and venture into the outside world, and Jubei gives a special request for her to stay close to Ragna. As they reach Ibukido, however, she runs off after being distracted by an insect, leading into the events of Chronophantasma.

In Chronophantasma, her Overdrive is Almost Becoming Two!, a former super of hers which produces a shadow image of herself that doubles the amount of hits her attacks dish out.

Voiced by: Kenji Nomura / Jamieson Price

A giant man-cyborg on steroids. Tager was an Ikaruga Federation commander at one point until he suffered major injuries during the Ikaruga Civil War. He was modified and healed by Kokonoe with cybernetic implants and demon genes, and now works for a secret organization known as "Sector Seven". His main objective involves bringing Hakumen to Kokonoe. After succeeding, Tager is sent out to capture Noel in Continuum Shift.

In Tager's Continuum Shift story, he meets with Makoto, who is revealed as a double agent in the NOL actually working for Sector Seven, and she hands him important data that Kokonoe had ordered to be delivered to him. He accidentally bumps into Hazama, who uses Ouroboros to jog his memories as a soldier in the Ikaruga Civil War. In the True Ending, he is seen escorting the now-deserter Noel and Makoto onto a private airship headed for Ibukido.

His Drive ability, Voltic Battler, magnetizes the opponent and allows him to draw him/her closer with certain attacks. His Astral Finish makes him do a ridiculously exaggerated version of his Distortion Drive in which he lifts the opponent high into the sky and crashes them down into the Earth.

In Chronophantasma, his Overdrive is Voltic Field, which places a magnetic field around the entire stage and forcing the opponent into a constant state of being magnetized.