[Credit] 1. Too hard (Feat. HEO DANIEL) Lyrics by SERO DAY, HEO DANIEL Composed by Olee, SERO DAY, HEO DANIEL Arranged by Olee 2. 실수 Lyrics by SERO DAY Composed by Unidentified boy, SERO DAY Arranged by Unidentified boy All songs Mixed & Mastered by SERO DAY