He has played with bands such as Primus, Guns N' Roses, Praxis, and Godflesh, and with other performers such as Tom Waits, Serj Tankian, Bill Laswell, Bootsy Collins, and Buckethead.

[1] As a teenager, Mantia became interested in such artists as James Brown, Led Zeppelin, and Jimi Hendrix, acts that featured groove-heavy sounds.

Because of his 'obsessive' study of the drum book Portraits in Rhythm by Anthony J. Cirone, Mantia was given the nickname "Brain" by members of his high school concert band.

[2] In the early 1990s, he joined Praxis, a musical project led by Bill Laswell and initially featuring Bernie Worrell, Bootsy Collins and Buckethead.

After leaving the band, Mantia made a guest appearance (alongside fellow former GNR member Robin Finck) at Guns N' Roses' House of Blues West Hollywood show on March 12, 2012.

[15] However, with Les Claypool and Larry LaLonde auditioning for "the greatest drummer on Earth" in Primus,[16] Mantia did not officially rejoin the band.

Brain and Melissa composed part of the soundtrack to the video game Infamous 2, for which they were nominated for "Outstanding Achievement in Original Composition" by the Academy of Interactive Arts and Sciences awards.

[18] Other video games the duo worked on include, Midnight Club 2 , PlayStation Home, ModNation Racers, Twisted Metal, Fantasia: Music Evolved and Infamous: Second Son (received the nomination Original Dramatic Score, Franchise at the 2014 NAVGTR Awards, shared with Marc Canham and Nathan Johnson).

[23] DW Collector's Series Maple drums in Tony Williams Yellow Lacquer with Custom Yellow Hardware 18x24 Bass Drum 8x12, 9x13 Toms 16x16, 16x18 Floor Toms w/ Legs 6x14 Edge Snare 9000 Single Bass Drum Pedal 9500 Hi-Hat 9300 Snare Stand 9700 Straight/Boom Cymbal Stand (x6) 9900 Double Tom Stand (x2) 9100 Throne Zildjian 14" A Mastersound Hi-Hats 19" A Medium Thin Crash (2) 20" K CrashRide 20" A Deep Ride 20" A Medium Thin Crash 22" Oriental China "Trash" Akai MPC 60 II, 3000 LE, 4000 Technics SL-1210MKZ Turntables with a M44Gs stylus Vestax PMCO5PRO DJMixer