A four-chapter prequel series, titled As the Gods Will Zero, was published on Kodansha's Magazine Pocket app and website from January to February 2017.

During a day at high school, Takahata Shun witnesses the explosion of his teacher's head, after which he and his classmates find themselves forced to play children's games, such as Daruma-san ga koronda, with deadly stakes.

Shun and Amaya try to kill him with magical "bombs" used for one of the games, but they get wounded by their own weapons and as a result are thrown out, on the verge of death, for trying to cheat God.

The god of the second series, Sein Kami, is killed midway through the story, impaled by giant school tools when his sister Acid Mana finds his games to be too "boring".

The last remaining survivors (Ushimitsu, Akashi and Amaya) become gods but realize they cannot bring back all the people who died during the games (only their memories of them, or empty shells/puppets).

Mana develops her abilities for hundreds of millions of years, until she is able to create a perfectly replicated Earth, allowing her remaining friend to return to his family.

Later, she and Sein Kami, whom she created as a brother, enter the version of the Earth in the "most boring era" and grant Kamimaro his Tomfoolery, thus starting the entire story.

[15] A four-chapter prequel story, titled As the Gods Will Zero (神さまの言うとおり零, Kami-sama no Iu Tōri Zero), was published on Kodansha's Magazine Pocket app and website from January 27 to February 17, 2017.