The Original Demon「原初の魔神, Gensho no Majin」 was an ancient demon created by the Demon King. After a failed rebellion attempt against the Demon King for his throne, he was divided in body and soul into two lesser Demons, Chandler and Cusack, as punishment.
The Original Demon has a centaur-like body, but with a white feline lower body instead of a horse, with two strange appendanges for tails and four arms. He wears redish armor only on his upper body.
His facial appearance is mostly unknown due to his helmet, which resembles butterfly wings, covering both of his eyes, leaving his green (blue in the anime) flame-like hair, nose and mouth exposed. He has a long white beard and sharp teeth.
The Original Demon seems confident in his own strength due to aiming at the throne of the Demon King, as well as having treacherous traits by instigating a rebellion. He seems to express some form of guilt over his past actions, calling himself a sinner. He apparently no longer seeks the throne, instead fighting to ensure Meliodas, who was Chandler's student, became Demon King and expressing joy when the time came and quick to anger and intervene when Merlin tries to stop it. He has shown himself to be very arrogant, mocking Escanor for being inferior despite his power being close to its peak and also taunting his enemies for being doomed to die at his hands.
Later during his battle against the Sins and Mael, the Original Demon is revealed to still have retained some traces of the personality traits of Cusack,as seen when he began to hear the inner thoughts and feel the lingering feelings of intense loyalty he felt for Zeldris and at the same time also retained traces of Chandler who similarly to Cusack also retained his powerful devotion to Meliodas,putting immense pressure on the Demon due to their inner struggle putting pressure on his own personality.
At some point prior to the formation of the Ten Commandments, the Demon King created the Original Demon and gave him some of his power as his most trusted retainer to allow him to rule over the Underworld, until the Original Demon started a rebellion against the king to take the throne for itself but failed. As punishment, the Demon King divided him in body and soul into two, Chandler and Cusack, and made them the instructors of his two sons to raise them to be the next candidates for the title of Demon King.
When the battle against the Assault Force turns in the wrong way for them, Chandler and Cusack decide to finally fuse together into their original form. As the Original Demon surges, the dark field created by Meliodas and the Commandments' is dispelled.
The Original Demon starts a fierce fight against Escanor. When Escanor receives a big slash in his chest after their clash, the Original Demon mocks him for still being inferior despite Escanor being at his peak. Escanor then uses his Cruel Sun, but the Original Demon blocks it with his shield. He rebuffs Escanor's claims of him and Merlin being enough, claiming that their deaths are already decided, and no one could come fast enough to save them. Merlin then attacks him with Exterminate Ray, but the Original Demon easily overpowers and severely injures her with his energy breath and then gives Escanor serious damage with a kick of his back legs. However, before he can finish Escanor, the Original Demon senses that something is coming. An enormous flying object comes to the scene, revealed to be Chastiefol, that the Original Demon barely managed to react to.
The Original Demon is able to block Chastiefol with his shield and cut its blade with his swords. King then changes Chastiefol into Sunflower, releasing a massive explosion over the battlefield. However, Zeldris protects the Original Demon cancelling the attack with God and tells him to focus on Escanor and Merlin while he faces King. When the Commandments arrive, the Original Demon smiles and claims for the birth of a new Demon King.
There, Merlin refuses to give up and prepares to use Chrono Coffin, which both Zeldris and the Original Demon recognizes with disbelief as the forbidden art capable of suspending time. The two are preparing to take down Merlin before she completes the spell and leaves the cocoon suspended in time. However, the Original Demon is intercepted by Escanor, who is preparing to protect Merlin. However, with Escanor now weakened, the Original Demon easily gains the upper hand and brutally injures him before he uses Death Drive to give the final blow, sending Escanor flying a great distance. However, before he could kill Merlin, the Original Demon is restrained by Ludociel who uses Ark to stop his attack.
As Ludociel manages to contain all his attacks, the Original Demon receives great damage from his Lightning Spree. The Original Demon responds with Hellblaze Omega, but Ludociel easily undoes his attack and hits it with Sparking Drive. The Demon launches another Hellblaze Omega that this time gives more work to Ludociel to contain. With a smile, the Original Demon receives several attacks from Ark and then launches a third Hellblaze Omega that manages to push back Ludociel.
The body of the Original Demon begins to break apart, leading him to reveal his true power Crisis that makes him stronger as his life runs out. He explains that by going against his punishment and returning to his original form, his flesh and bone is approaching its imminent destruction. In launching himself against Ludociel, he claims that he is pleased to sacrifice his life for the birth of the new Demon King.
After hearing Mael try to dissuade Zeldris from making Meliodas the Demon King, a part of Cusack's conscience tells the Original Demon that they should not let that happen either. Ignoring him, the Original Demon is shot against Mael, who uses his Greatest Sun to catch him in a fiery explosion.
After barely surviving Mael's attack, the Original Demon is once again divided into Chandler and Cusack.
Later after the death of Chandler and death of Cusack, it can be summarized that the Original Demon itself is now permanently dead.
Abilities and Equipment
The Original Demon is immensely powerful, as Merlin, after feeling his magic power, claims that they lost any chance of victory.
The Original Demon's power is so great that he was capable of dispersing the massive sphere of darkness created by Meliodas with his magic power alone, even after the latter absorbed five Commandments. He was so powerful that Diane, King, and Elizabeth Liones, were able to feel his power from miles away.
The Original Demon possesses immense physical strength, as shown when he easily fights on par with Escanor in a physical duel and overwhelms him, although it was noted that he was past his peak as noon had passed. He possesses immense levels of endurance and durability, as shown when he remains completely unharmed after battling Merlin and Escanor in his day form, and is able to withstand mutiple injures from Ludociel, leader of the Four Archangles, and continues to fight. He can fire a beam of energy from his mouth that is capable of overwhelming Merlin, an extremely powerful magician, and heavily injures her. He is also extremely skilled in swordsmanship, able to fight evenly with Escanor while wielding Rhitta.
終局, Kuraishisu」: The Original Demon's innate magic power. This ability allows his power to constantly increase while taking damage.
- Death Drive「
死衝, Desu Doraibu」: The Original Demon points his sword cane towards his opponent and sends them flying with incredible force.
獄炎, Herubureizu; literally meaning "Hellfire"」: A mysterious ability possessed by the Original Demon that allows him to generate black flames. The technique also has the additional effect of nullifying an immortal's regeneration.
- Sword Cane: Due to possessing half of Chandler's body and soul, the Original Demon carries a sword cane.
- Dual Sword Hilts: Due to possessing half of Cusack's body and soul, the Original Demon carries two identical sword hilts which he channels his darkness through to create two blades.
- Shield: The Original Demon carries a shield, which has the combination of Chandler and Cusack's initial demon marks. His shield is strong enough to withstand a point-blank Cruel Sun attack from Escanor, and stop an attack from King's New True Spirit Spear Chastiefol.
The Original Demon was created by the Demon King and gave him some of his power as his most trusted retainer. But the Original Demon betrayed him and started a rebellion to take the Demon King's throne. After he lost, the Demon King split him into two beings: Cusack and Chandler. After the split they were burdened with the task of training the two princes to become the next Demon King, both showing tremendous loyalty and pride in the ones they chose to train, Chandler training Meliodas and Cusack training Zeldris.