A sneak peek of the song surfaced when lead singer Hayley Williams posted lyrics on the band's Official Fan Club.

On March 24, 2016, the song was certified gold by the Recording Industry Association of America (RIAA), for sales exceeding 500,000.

[7] James Montgomery of MTV noted the number of times that the word "you" is used in the lyrics of "Monster" because of its subjectivity.

He suggested that the song is about former members of the group Josh and Zac Farro, since they left the band in 2010 and it is the first track without them.

[8] According to Jon Blistein of Billboard, the song has elements of grunge, such as loud-soft dynamics, big vocals, and loud, crunchy guitars.

[12] The single cover was described by Becky Bain, as containing the three members of Paramore, Hayley Williams, Jeremy Davis and Taylor York, standing in a dark tunnel where a light at the end faces the band.

Hayley opens her eyes and begins to sing as the video cuts to the band performing in a concrete room while kicking and punching the walls.