Vangelis conceived the idea of their third, 666 (1972), a double concept album based on the Book of Revelation. It is widely recognized as a progressive-psychedelic rock classic. After increasing tensions during the recording of 666, the group split in 1971. Vangelis would produce future albums and singles by their singer Demis Roussos.
In 2016, he and Raney Shockne wrote and composed the music to the video game Tron RUN/r. The soundtrack album was released on 31 May 2016. In October 2016, Moroder produced "One More Day" for Sistar, a Korean girl group. They debuted the song live on 8 October, at Korea's DMC Festival 2016, with Moroder being present in the audience.