Goka! Gokai!? Phantom Thief!

is a song by Hello, Happy World!

It is the title track for their 2nd single, with YAPPY! SCHOOL CARNIVAL☆彡 and Sekai Nobbinobi Treasure! as the coupling tracks. It was released on February 14, 2018.

It is the gift song for the event Happy Phantom Thief & The Luxury Cruise, and was also one of the challenge songs for the event A Dreamy Promenade.

A recorded live version performed by Raychell, Natsume, Kurachi Reo and Otsuka Sae during the THE THIRD 1st Live was included in the live album released on September 26, 2018.

It was used as one of the insert songs for the 4th episode of BanG Dream! 2nd Season.

It was written by Oda Asuka, and composed and arranged by Fujima Hitoshi.

Chart Performance

 * On Feburary 14, 2018, Goka! Gokai!? Phantom Thief! ranked 12th in the daily singles ranking in Oricon.
 * On February 15, 2018, Goka! Gokai!? Phantom Thief! ranked 7th in the daily singles ranking.

Live Performances

 * March 25, 2018: THE THIRD 1st Live
 * July 17, 2018: THE THIRD 2nd Live
 * December 7, 2018: Brave New World
 * July 14, 2019: Heaven and Earth Day 2
 * February 9, 2020: Craziness