The 2010 Sleepthief song “Empyrean” featuring Suzanne Perry’s classic glossolalia style vocals is included on the 2015 expanded version of Labyrinthine Heart. This song was previously only available on a Barnes & Noble exclusive compilation CD, making this the first time it’s been available on streaming services. “Empyrean” is 1 of 4 bonus tracks added to the 2009 album, which also features updated artwork.

Utah artist, SLEEPTHIEF, released a brand new collaboration with Suzanne Perry. Their song, “Empyrean,” is featured on a Barnes & Noble exclusive CD produced by Neurodisc Records, called Beauty 2: Music that Touches the Soul. This various artist compilation is a follow-up to Beauty: Music that Touches the Heart which featured several songs by Sleepthief collaborating with vocalists Kristy Thirsk, Nicola Hitchcock, and Jody Quine.