Fellow Roadrunner United captains - Machine Head's Robert Flynn and Trivium's Matt Heafy - rocked out on stage together earlier this week (8/24) to some metal classics. Trivium was playing at the Barfly in London at the pre-Kerrang! Awards show when Flynn grabbed a guitar and joined the band on stage towards the end of their set. Together, they jammed through covers of SEPULTURA's "Roots," METALLICA's "Creeping Death," PANTERA's "Walk," and IRON MAIDEN's "The Trooper." The collaboration came to fruition as the Matt & Robert have been working closely together on the forthcoming Roadrunner United release, the All-Star Sessions. This full length release, in stores October 11th, is a 'master-class' in hard rock/metal. Boasting 57 artists from 45 of Roadrunner's past and present bands, the album will contain original tracks that are collaborations between numerous Roadrunner stars. Four central musicians were originally chosen to produce and write the songs. Joey Jordison (Slipknot), Dino Cazares (ex-Fear Factory/Brujeria), Robert Flynn (Machine Head) and Matthew Heafy (Trivium). These four musicians play on the songs they have written and have also assembled a unique team of artists to appear on each track. In order to cover as wide a spectrum as possible, no musician has played for more than one writer/producer and each song features a different vocalist.