So much has been written about "Big 4" of metal: Metallica, Megadeth, Slayer and Anthrax. The most popular and influential thrash bands each established themselves with platinum records and endless tours. Slayer and Anthrax joined forces on numerous tours long before Slayer decided to hang up their spiked wristbands.

In addition, Megadeth, Slayer and Anthrax played together on the Clash of the Titans tour in 1990 and 1991 and the package thrash fans waited decades for, The Big 4 European tour, featuring Metallica, Slayer, Megadeth and Anthrax, took place at European festivals in 2010. Select U.S. dates were staged in 2011, most memorably at Yankee Stadium, where the hometown heroes, Anthrax took the stage wearing New York Yankees uniforms.

The only problem with constantly recognizing the Big 4 is that there are many more vital thrash bands that have been downplayed. As history has revealed, Exodus' lead guitarist, Kirk Hammett, wound up in Metallica after Dave Mustaine left the band and their main songwriter/guitarist, Gary Holt, filled in for Slayer's late, great Jeff Hanneman from the moment he became unable to perform to the day he died, and long after.

In a recent interview with TwinMuix.com, Anthrax bassist Frank Bello was asked who he would add if the Big 4 became the Big 5. "Exodus, because [they] have been there from the very beginning," he said without hesitation. "It is hard because we have all been there for a really long time. Testament, Overkill -- there are a lot of great bands."

Holt echoed Bello's sentiment in a September 2017 interview Loudwire. "We are arguably the first thrash band and the only other one you could really make an argument with is Metallica and I think at the time we were both starting to do our thing and neither of us knew the other existed. So yeah I mean we definitely made a big contribution because we helped create it. Big 4, Big 5, Big 10...I don't know we were the first, so I think we have every right to be there."

Holt added that many fans and critics often overlook bands outside of the California and North America. "I've always said when everybody talks about the big this or that they always like forget about the Germans," Holt said. "Kreator, Destruction and Sodom were there in the very beginning too and they were there earlier and before a lot of the American thrash bands that people like throwing in these hypothetical arguments. I don’t limit it strictly to United States soil. I think the Germans have should have a voice in this as well."

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