Identity: Challenge

On February 7, 2021, it was announced the group would release their second extended play Identity: Challenge on February 24.^[1] On February 17, the track list was released, with "All or Nothing" announced as the lead single. The next day, the highlight medley video was released. Music video teasers for the lead single were released on February 20 and February 23, respectively.

Identity: Challenge consists of five tracks about the group becoming one by overcoming challenges and trials.^[2] The lead single "All or Nothing" is a hybrid trap song produced by member Jang Dae-hyeon in order to show a strong and powerful performance. The second track "Breathing" is a future bass song that expresses the desire to approach someone who breathed life into them while they were in the dark and gave them hopes and dreams. The third track "Dancing in the Dark" is described as overcoming difficulties as if dancing in the dark and finding someone like a dream. The fourth track "Diffuser" is a sweet R&B song that expresses the desire to comfort and strengthen others by becoming a perfume and covering them warmly. The fifth track "Winter, Flower" is a R&B ballad, described as an emotional expression of gratitude towards their fans named RUi.^[3]

Following the release of Identity: Challenge, WEi held an online showcase on the same date to introduce the extended play and communicate with their fans. The group performed "All or Nothing" and "Diffuser" during the showcase.^[3] The group's promotions for the song "All or Nothing" began on February 25, 2021, on Mnet's M Countdown. The B-side track "Diffuser" was also performed during the group's promotions. "Winter, Flower" was performed on KBS2's You Hee-yeol's Sketchbook on March 5.