The franchise was launched as an ambitious "entertainment project" featuring a tragic fantasy story of two souls sharing a single fate. It included:
: A mobile RPG where players lead adventurers through dungeons using a card-based skill system. Note: Official service for the game ended on May 31, 2018.
: The project also spanned a web anime, manga series, and a novel titled Dia Horizon: Akatsuki no Keiyakusha . How to Open a .7z File