A decade on Begg is providing the soundtrack to blackSKYwhite's latest voyage into darkness, OMEGA, now running at the Assembly Rooms following try-outs at Glastonbury Festival where the company, led by director Dimitri Aryupin, are regulars.
Described as 'a hoochie-coochie carnival for the end of time,' OMEGA involves a roll-call of freaks, creeps and mythical beasts who present an entertainment that becomes a matter of life and death.
"It's never anything less than unsettling," says Begg. "There's never any straightforward narrative, and you're never quite sure what's going on at times, but it all resonates on a great emotional level."
OMEGA is Begg's second collaboration with blackSKYwhite, after Aryupin approached him "out of the blue" to work on a show called E.S.M. (Eve, Salome, Mary).
When Aryupin approached him again to work on OMEGA, Begg jumped at it.
He said: "I'm usually happy to work with my own obsessions, but here I had to put myself on the back-burner, and work with Dimitry's obsessions.
"There are elements of Russian mythology and old testament bible stories in there. It goes much deeper than just terrifying people."
Begg's own back catalogue includes three albums in partnership with Deryk Thomas as Human Greed, and contributions to Fovea Hex, the experimental ensemble based around the voice of Clodagh Simonds, who once sang backing vocals for Thin Lizzy, as well as appearing on Mike Oldfield's Hergest Ridge and Ommadawn albums.
Fovea Hex's 2011 Here is Where We used To Sing album also featured contributions from Brian Eno, who is speaking at the National Museum of Scotland tomorrow, as part of the Movements series of talks in the EIF programme.
OMEGA is showing at the Assembly Rooms until Sunday.
Michael Begg plays a solo concert at Summerhall on Saturday.