Devilman vs Hades

Devilman vs Hades (デビルマン対闇の帝王 Debiruman tai Yami no Teiō lit. Devilman vs Emperor of Darkness) is a manga by Team Moon for the 40th anniversary of Devilman and Mazinger. It was released on November 2012 for Monthly Young Magazine. Characters and villains from both series are featured in an original story about the Akira Fudo trying to find the soul of his lost love, Miki Makimura.

Plot
The world was destroyed from the war between Demons, Humans, and Devilmen. Akira, now trapped in the underworld, seeks the soul of Miki. While there he hears about the ruler of the underworld, the Emperor of Darkness (aka Hades) and his power to bring back the dead. Taking a risky chance, Akira attempts to track down Miki's soul and the Emperor of Darkness in order to bring her back to life.

However, Dr. Hell is beeseeching the underworld for the power to get his revenge on his hated enemy, the Mazinger. Some of Akira's old enemies such as Sirene and Jinmen are also there for payback. With all of the activities, Hades vows to put a stop to Akira for his defiance.

Trivia

 * The fact that the Emperor of Darkness is also named Hades is a reference to his counterpart in Shin Mazinger.