Metallica‘s plan to rival Pink Floyd’s The Wall may be delayed due to the recent success of the Big Four shows at Sonisphere Festival. The Big Four – Metallica, Slayer, Megadeth, and Anthrax – may plan to do more shows together. Lars Ulrich says, ““So I would champion trying to do this [the Big Four tour] in 2011 or 2012, obviously in England and the United States. It’s just a matter of logistics. I don’t think there’s anybody involved who considers there’s a sell-by date on this.”

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