In the future, the "Metal Fight" games are the most popular televised sport in the world and many robot contestants compete for the title of Best Metal Fighter in the World. Kurenai Ken, along with teammate Saeba Shoko (who was, at first, adamant), pilots the Super Robot Fighter, Red Baron and enters the contest with dreams of becoming its champion. He must, however, face an army of other rivals from around the world including Kaizer (who is, in fact, Shoko's supposedly "lost" father, Tetsuo Saeba), the Tetsumen Tou ("Iron Fist" - a reference to the original Red Baron TV series) doctors, Tiger and ShinRon.

Despite standing at the zenith as the strongest exorcist, Haruyoshi Kuga sought even greater power, which led to his demise at the hands of those who envied his might. As he draws his last breath, he casts a spell that allows him to reincarnate and swears to become more cunning, hoping that all his efforts will prove useful in his next life. Haruyoshi is soon reborn in another world as Seika Lamprogue, an illegitimate son of a noble family that prides itself on magic. However, his new family largely ignores him due to his lineage and magic deficiency. Nevertheless, the unbothered Seika leverages the knowledge from his previous life to make numerous valuable allies. As he begins to explore the true limits of his abilities, Seika must also be wary of the consequences that tarnished his past and avoid repeating the same mistakes.

For as long as he can remember, Minoru Kagenou has been fixated on becoming as strong as possible, which has led him to undertake all kinds of rigorous training. This wish, however, does not stem from a desire to be recognized by others; rather, Minoru does everything he can to blend in with the crowd. So, while pretending to be a completely average student during the day, he arms himself with a crowbar and ruthlessly thrashes local biker gangs at night. Yet when Minoru finds himself in a truck accident, his ambitions seemingly come to a sudden end. In his final moments, he laments his powerlessness—no matter how much he trained, there was nothing he could do to overcome his human limitations. But instead of dying, Minoru reawakens as Cid, the second child of the noble Kagenou family, in another world—one where magic is commonplace. With the power he so desired finally within his grasp, he dons the moniker "Shadow" and establishes Shadow Garden: a group whose sole purpose is to combat the enigmatic Cult of Diablos, an organization born from Cid's imagination. However, as Shadow Garden grows in both membership and influence, it becomes increasingly apparent that the Cult of Diablos is not as fictional as Cid had intended.

Centuries ago, the land of China was full of magical spirits. Those who could utilize the power of spirits were called Exorcists. Their duty was to prevent the Great Diablo, a demon showed up once every millennium, from plaguing the world. In Han Dynasty, however, in a catastrophe known as The Oblivion, all magical spirits vanished overnight. Having lost their powers, Exorcists became a thing in the past. Later, during the incessant war between Qin and Jin kingdoms, the resentful spirits of those who died in vain became the nutrients triggering the revival of the Great Diablo. In order to stop the demon, Chen Xing, the last surviving Exorcist, starts a journey with "Lamp of the Heart", a magical artifact that lives in his soul. He is to travel to Xiangyang City to find Xiangshu, who is destinied to join him to expel the demon.