The primary antagonist of the series. While initially stated to be the Mainland's representative after the Lost Ground chaotic second uprising, Mujo soon defects and becomes an independent and unstoppable renegade thanks to his own greed and endless thirst for the ultimate power, which he speaks of frequently as the "Other Side".
This Alter User from the Mainland boasts extreme power over others with his own Alter, merely called "Absorption". This power allows him to absorb the power of other living things and literally imagine a physical kind of Alter in any way he chooses, this is linked to his thirst for ultimate power, which he speaks of frequently. While initially stated to be the Mainland's representative after the Lost Ground chaotic second uprising, Mujo soon defects and becomes an independent and unstoppable renegade thanks to his own greed and endless thirst for the ultimate power, which he speaks of frequently as the "Other Side". In episode 21, Mujo (he is often referred to by his last name) comes in contact with the "Other Side" after coaxing Kazuma and Ryuho to once again open the door and manages to absorb the power of the Crystallized Alter Embodiment which had killed Ryuho's mother. This grants him a nearly unstoppable new power that he uses to reform HOLY HQ and that also allows him to summon the Embodiment as a stand alone Alter. Mujo can even use this ability to enhance his own body, with his favorite method being to use both the Embodiment's powerful black and white drill-like arms to himself, calling them "Black Joker" and "White Trick", and usually referring to them as Light and Darkness or Heaven and Hell. In episode 24, while his Alter Embodiment handles Ryuho, Mujo is defeated by Kazuma's ultimate Alter form and is forced to take refuge in "the Other Side".
Thinking of themselves victorious, Kazuma and Ryuho reunite, only to be greeted by a monstrous new Kyoji Mujo, gleefully stating he has finally satisfied his unquenchable thirst for power at last. Armed with several new kinds of weapons, including some strange red lasers of some sort, he goes berserk, destroying even his own HQ just to kill both Kazuma and Ryuho. However, his merriment is quick to fade upon finding that his lasers have not even dented Kazuma or Ryuho's new Alter forms. Ryuho states that he's finally put the hatred of his past behind him and now it's Kazuma's turn. With a snicker, Kazuma casually strolls up to Mujo, taking several direct hits from his lasers without even flinching, stating that he cares nothing of the past or future, just about crushing any obstacle that currently stands before him. Mujo is mortified, nearly wailing with terror by that point as Kazuma finally delivers the finishing blow to the top of his head. His body slowly disintegrates before exploding into nothing. In the end, Mujo ends up losing the power he had so craved for his entire life in only a matter of seconds. Very little of his backstory was ever revealed, but it was stated that he grew up in the wastelands and willingly chose to be refined, due to his disgust of always living in the shadows of more "prosperous" Alter Users, such as Ryuho, and essentially all of HOLY as well, leading to his insatiable greed to possess absolutely everything possible.
He appears as one of the people to cheer Kazuma & Ryuho on as they face Galan Du.
Absorption: Kyoji's original "Alter" ability. Kyoji can freely drain the "Alter" energy from any user through either his breath or his hands, integrating their unique energy signature into his own body and enabling him to replicate at least a portion of their capabilities, while the targeted user has their very composition disentegrated (even powerful characters such as Kigetsuki could be dematerialized in seconds). After absorbing the powers of The Crystal "Alter", Kyoji could also implement an electric field onto the opponent, in order to paralyze and neutralize movements while "Absorption" is in effect.
- Electric Field: Stolen from "The Crystal". Kyoji can release electrical bolts from his palm, which then "wrap" around a target in a field of voltage, continually electrocuting them for the duration of the technique as they are paralyzed on the spot.
- White Trick & Black Joker: Stolen from "The Crystal". In mêlée combat, Kyoji primarily attacks by transmuting its arms into a distinctive color pattern: black on the right-hand side, white on the left-hand side. These converted limbs typically function by either unleashing a powerful and sustained electric shock on physical contact, or by being further transformed into high-velocity rotating drills to tear and pierce tough materials.
- Dimensional Travel: Kyoji is capable of opening up individual portals and freely traversing the tunnel into the "Alter" parallel dimension, and travel back into the real world.
- Electronic Technopathy: Stolen from the Elian Twin Clones. Following the destruction of the Alter Fortress' central reactor, Kyoji was able to restore power to the entire megastructure and all of its internal installations by entirely absorbing the "Alter" capabilities of the Elian twin clones.
- Summon Alter: Following the obtaining of its powers, Kyoji also gained the ability to freely call upon the assistance of The Crystal for combat.
Mutated Form: The mutation of Kyoji Mujo likely occured as a result of direct contamination through overexposure to the "Alter" dimension (though this is unconfirmed, outside of the fact that the parallel dimension was responsible). Mutant Kyoji appears incapable of using his standard "Absorption" effect, though again this is merely conjecture.
- Energy Tendril Swarm: The spines across mutated Kyoji's back glow a deep black coloration with a crimson red outline, before unleashing dozens to hundreds of energetic tendrils of the same color. The tendril swarm is omnidirectional and individual tendrils extend for at least several kilometers, smashing through any structural obstacles without loss of momentum and with Kyoji being able to distort the beam's direction in mid-air. The blasts disperse after a few seconds of stability. Only the most powerful characters ("Proud Fist" Kazuma and "Stage 3 Zetsuei" Ryuhou) can likely withstand this barrage.
- Giga Laser: Mutant Kyoji generates a medium-sized sphere of black energy with white and red outlines from the hole in his head, before unleashing a large beam from the sphere towards the opponent. Total environmental effects are unknown, due to "Proud Fist" Kazuma easily dispersing the energy, though it would not be entirely unreasonable to suggest its energy output is equivalent to the sum of the "Energy Tendril Swarm".