: Felix often highlights the "headache" (Meori apeuda) move and the addictive leg-wiggle sequence as the song's signature choreography. Musical Arrangements For musicians looking for sheet music or covers:
: Some versions, like the 2019 MBC Gayo Daejejeon Remix , incorporate theatrical elements like red ribbons and vampire-inspired concepts. Stray Kids Side Effects
Known for its chaotic and high-energy choreography, "Side Effects" is often cited as one of the group's most difficult dances. : Felix often highlights the "headache" (Meori apeuda)