Dark Schneider is the central protagonist of the story, a figure of immense power and equally immense ego. He is an ancient and legendary dark wizard, known as one of the most powerful beings in the world, and has lived for several centuries. He is a tall individual with long white hair and blue eyes, often seen in elaborate robes or armor, though he is also known for having little concern for modesty. His origins are shrouded in mystery; he may have been created by the wise men of the old world to pilot a massive mecha, or might be a fragment of a fallen angel or the son of Satan. What is known is that fifteen years before the main events, he led the Dark Rebel Army on a campaign to conquer the world, only to be defeated and sealed inside the body of a newborn baby named Lucien Renlen by a great priest.

The character is defined by his spectacularly selfish and hedonistic personality. He is vain, arrogant, greedy, reckless, and short-tempered, believing the world belongs to him and that he answers to no one. He is a notorious womanizer who dreams of an endless harem and is constantly chasing after women, yet he also has a softer, protective side that he typically shows only to a select few. This duality is a result of his long-term fusion with the kind and caring Lucien. Because of this link, he has become more compassionate than he once was, showing mercy to former enemies and developing genuine loyalty to his companions, even if he would never admit it. The one person who can truly control his wilder impulses is Tia Noto Yoko, the priestess whose kiss first unleashed him from his seal; he fears her temper and cares deeply for her opinion, willing to change his ways for her in ways he will not for others.

His primary motivation is the pursuit of his own pleasure and power, which includes his ambition to conquer the world. Initially, he only agrees to defend the kingdom of Metallicana to protect Yoko and get revenge on his former army for betraying him. Over the course of the story, his role evolves from a reluctant, chaotic ally to a more active defender, driven by his personal attachments. He reclaims his former generals, known as the Riders of Havoc, turning them back into his followers. His key relationships are central to his character. He shares a complex bond with Yoko, who he loves and respects, and with Arshes Nei, his adoptive daughter and long-time lover, for whom he has ripped out his own heart to break a curse. He also has an adversarial but loyal relationship with the ninja master Gara.

As a wizard, Dark Schneider specializes in fire and lightning magic, but is also a master of dark arts and spirit magic, derived from pacts with elemental spirits and demons. His power is nearly limitless, allowing him to cast spells that summon dragons, create cyclones of fire, or unleash massive explosions. Some of his most notable and destructive spells include Venom, which is known only to him, Sodom, Halloween, and Megadeth. He has admitted to a weakness for ice and cold magic, though he can still find ways to counter or utilize such elements. Beyond his spellcasting, he possesses superhuman strength, durability, and the ability to regenerate lost limbs. He has achieved a form of magical immortality, capable of reincarnating himself if his body is destroyed, as his existence is tied to three planes: the physical, spiritual, and soul.