Bellamy composed his first solo release, "Pray", for For the Throne, a 2019 compilation album of music inspired by the TV series Game of Thrones. In May 2020, Bellamy released his second solo song, "Tomorrow's World", inspired by life under lockdown during the COVID-19 pandemic. In June, he released an acoustic version of the 1999 Muse song "Unintended". Bellamy released a compilation of his solo work, Cryosleep, on July 16, 2021 for Record Store Day.
