[5][4] In late 1994, Tobias joined Guns N' Roses as a replacement for Gilby Clarke and played rhythm and lead guitar on the band's cover version of the Rolling Stones' "Sympathy for the Devil".
[7] Rose further explained that the intention behind bringing in Tobias was to help the band in the studio: "The public gets a different story from the other guys – Slash, Duff, Matt – who have their own agendas.
"[8]In 1997, Tobias began working for Guns N' Roses full-time in a studio setting, jamming and recording song ideas with keyboardist Dizzy Reed and then-lead guitarist Robin Finck, among others.
[10] In January 2001, Tobias made his live debut with Guns N' Roses as the band played their first concerts in eight years at Las Vegas's House of Blues and Rock in Rio III.
During that same year, Tobias' other band, Mank Rage, expressed interest in releasing an album consisting of material recorded prior to his tenure with Guns N' Roses.
In 2008, Guns N' Roses released Chinese Democracy, and Tobias was credited as a co-writer on seven songs, in addition to contributing arrangements, and guitar and piano parts.