If there was any doubt that things are cool between Anthrax and former guitarist Rob Caggiano, this video seems to clear it all up. At this week's 2014 Copenhell Festival in Denmark, Caggiano joined his former bandmates onstage to close out Anthrax's set with a performance of 'Antisocial.'

In early 2013, Rob Caggiano announced his departure from Anthrax. Having already manned lead guitar from 2001-2005 and again from 2007-2013, Caggiano was ready to move on and focus on his producing career. However, while working with Volbeat for 'Outlaw Gentlemen & Shady Ladies,' the Danish band recruited Caggiano as a new full-time guitarist. In turn, Anthrax brought on Jon Donais of Shadows Fall as their new axeman.

Both Anthrax and Volbeat have been enjoying continued success ever since the lineup changes, and although Anthrax drummer Charlie Benante once called Caggiano's decision "sketchy," no barbs have been publicly thrown by either side.

Although Volbeat did not play the Copenhell Festival, the band is currently running the European summer festival circuit. With Caggiano finding himself free on June 11, the guitarist performed only for the short reunion, allowing for an even bigger surprise.

Watch Anthrax jam 'Antisocial' with Rob Caggiano at the 2014 Copenhell Festival above!

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