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In an interview with Loudwire, Slayer guitarist Kerry King commented on Dave Mustaine's request for more shows by the Big Four of Thrash – Metallica, Megadeth, Slayer, and Anthrax. King said he was interested in the possibility, but admitted it would be difficult to coordinate the bands' dates
“Personally, I enjoyed the Big Four tour much more than I thought I would. When they came up with the idea, I thought, 'Oh, this will be really cool for the fans,' but then I went and got on stage… We’ve been a part of this for 20 or 30 years, but participating in the tour was much more fun than I expected, it was really great.”.
I'm totally in favor. I just don't know if there will ever be a time in our lives when these four headlining bands will have the same amount of time between them to make it happen. But I'm totally in favor, I loved doing it.”
Rumors of a possible Big Four tour surfaced in November when Dave Mustaine took to Twitter to ask for the bands to reunite. Metallica bassist Robert Trujillo has also commented on the possibility .