"Butter-Fly" was the theme song to the 1999 film
Digimon Adventure, performed as a ballad. "Butter-Fly" was later re-worked as a rock song, and its rock iteration became the opening theme song to the
television series of the same name. The success of the song gave Wada the title "Immortal Butterfly Anime Song Singer."
Other versions "Butter-Fly (Strong Version)" was released on April 22, 2009 to commemorate the 10th anniversary of the
Digimon franchise as well as the 10th anniversary of his debut with the song. It was his first single in three years after "Hirari" and charted on
Oricon Weekly Singles for one week. and the single was his last release before his death on April 3, 2016. A second version of "Butter-Fly (tri. Version)" was released as a tribute on May 1, 2018 as the ending theme to
Digimon Adventure tri.: Chapter 6: Future, the final installment to the
Digimon Adventure tri. film series, as well as the final part of the film. The song was performed by
AiM,
Ayumi Miyazaki, and the eighteen main cast members of
tri., along with posthumous archive audio of Wada. ==Reception==