Name: Senyuu
Genre: Action, Adventure, Comedy, Fantasy
Released: 2013

Story

TV short by Ordet — Winter 2013, 13 episodes, Finished.

Long ago, there lived an evil being who reigned over the world through fear, called Satan Rchimedes. He invaded the human world with his many demon underlings, spreading madness and chaos everywhere. One thousand years ago, this menace was sealed by the hero Creation, and peace returned to the world. Then, one day, a great hole suddenly appeared on the surface of the world, and a vast number of demons appeared. The king discerned that the menace Satan had returned after being sealed away for a thousand years, and decided to send the hero's descendants to battle him. He found 75 men.

Synopsis via AniList (English).