The original concept was developed by Marvelous and a three-person unit of writers known as Speakeasy made up of Kōshi Tachibana, Sō Sagara and Wataru Watari.
Children who were evacuated to a cold sleep facility during the invasion by the Unknown several decades ago wake up from their slumber and learn that their bodies developed supernatural abilities called "World".
The second series is Itsuka Sekai o Sukū Tame ni: Qualidea Code (いつか世界を救うために -クオリディア・コード-), written by Kōshi Tachibana and illustrated by Kiyotaka Haimura.
The fourth series is Dōdemo Ii Sekai Nante: Qualidea Code (どうでもいい 世界なんて ‐クオリディア・コード‐), written by Watari and illustrated by Saitom.
Anime News Network (ANN) had four editors review the first episode of the anime:[23] Paul Jensen and Nick Creamer gave similar praise and criticism to the battle sequences and cast of generic archetypes, with the former noting how the episode has a sense of humor about its given genre and the latter commending the writers for not rushing things to explain the series' universe through lengthy exposition or interpersonal character melodrama; Theron Martin praised the character interactions, setting and action scenes for having decent value to them but wanted to know more about the cast besides Ichiya and the direction being taken for the overall plot moving forward.
The fourth reviewer, Rebecca Silverman, was critical of the story execution throughout the episode and the main cast having little in the way of engaging character traits or motivation for the viewers to care about them.