Hwang Dong-jun and Son Jun-hyung participated in Mix Nine,[2] only the latter passed the audition.

[3] On November 25, 2020, Maroo announced that the group's second mini album, Pre Episode 2: W.all on December 10, with the lead single "W.all".

On January 18, they then performed a free busking show in Venice Beach, Calif.

The next day, they held a fansign event in San Francisco, at the local Kpop store SarangHello.

Ghost9 released their sixth EP Arcade: V on April 7, with the lead single "X-Ray".