Apollyon Sun was a Swiss industrial metal band formed in 1995 by singer/guitarist Tom Gabriel Fischer and guitarist Erol Unala. Following the dissolution of Celtic Frost, Fischer's previous group, Apollyon Sun released their first EP, God Leaves (And Dies), in 1998 through Mayan Records. The band gained attention with their five-track Industry Demonstration CD in 1997 and were subsequently managed by Rod Smallwood and Merck Mercuriadis. Their debut full-length album, Sub, was released globally in late summer 2000 after extensive recording sessions at various studios. Notable contributions include soundtrack work for the BBC TV show City Central and Dave Grohl's Probot project, featuring the song "Big Sky". The band performed their first international concerts in fall 2000. Apollyon Sun disbanded in 2001 when Fischer invited Unala to contribute to the reformation of Celtic Frost.