Composition
Mic On contains three songs. The EP opens with "1,2,3 Eoi!", a "masterful" track incorporating electronic and hip-hop elements, with the group's vocals, it adds a smooth, jazzy texture that complements the vocals in the chorus.[1] Followed with the title track "Illella", it opens with "bright" ad libs and "rich" vocals over a powerful reggaeton instrumental mixed with guitar riffs and "resounding percussion" in its arrangement.[1] The closing track "L.I.E.C." is a nu-disco song, NME noted that the song is similar in its production to the group's single "Um Oh Ah Yeh".[1]