Interested in the burgeoning local punk scene as a teenager, Mosely befriended bassist Billy Gould and the pair became brief members of an obscure local band called the Animated. Upon the group's breakup, Gould formed another outfit, Faith No More, while Mosely fronted Haircuts That Kill. When Faith No More was left singer-less in 1984 (a pre-Hole Courtney Love had just split), a tryout was arranged for Mosely. Despite his knack for wandering off-key, Mosely's charisma got him the job, as the group (which would eventually include keyboardist Roddy Bottum, guitarist Jim Martin, and drummer Mike Bordin) played regularly around the San Francisco area.

After a pair of albums created a buzz in the alternative rock underground (1985's We Care a Lot and 1987's Introduce Yourself), Mosely found himself at odds with his bandmates due to his unpredictable behavior both on and off the stage, which led to his ousting from the band in 1988. Faith No More would continue on with a new singer (Mike Patton) and score a hit straight away with their next release, The Real Thing, while Mosely attempted to work his way back into music. Early in the '90s, Mosely joined up with Washington, D.C., hardcore icons the Bad Brains, but before anything could be recorded by the Mosely-led lineup, the singer bailed (complaining that the group wanted him to sound too much like their previous singer, H.R.). Mosely then formed another group, Cement, a quartet that issued a pair of albums, 1993's self-titled release and 1994's Man with the Action Hair, before splitting as well.

Mosely spent the next decade on a sort of public musical hiatus, relocating to Cleveland to raise his two daughters and writing and compiling new material while working as a chef. He resurfaced in 2009 and released the album Will Rap Over Hard Rock for Food, which saw him teaming up with multi-platinum producer/engineer Michael Seifert. Demos for Sale, a collection of alternate mixes and demos from the Will Rap Over Hard Rock for Food sessions, arrived in 2016. ~ Greg Prato