Nana Mizuki will be releasing a new single titled "WONDER QUEST EP" on September 26.
The new single will be a quadruple A-side single. Each of the 4 songs will have tie-ups of some sort.
One of the new songs, titled "Birth of Legend", will be used as the theme song to the smartphone app "Kokyo-sei Millionaire System", while another song will be used as the CM song for "Hungry Hungry".
Mizuki explained that all 4 songs on the single have a common theme "to explore". Furthermore, listening to the songs will be like going on a quest, hence the title of the single.
This will be Mizuki's first new single in over a year. Her last single "TESTAMENT" was released on July 19, 2017.