The lineup for the inaugural Ozzfest Japan just keeps getting bigger. Event producers have just announced they've added Stone Sour , Slash , Tool and Deftones to a roster that already includes headliners Black Sabbath and Slipknot .

“We’ve assembled an amazing lineup for the first-ever Ozzfest Japan,” said Ozzfest founder Sharon Osbourne in a statement. “Black Sabbath, Slipknot, Tool, Slash, what more could you ask for? And we still have plenty of surprises to come. The Ozzfest Japan line-up will rival any of our previous festivals.”

Ozzfest Japan runs May 11-12, 2013 at the Makuhari Messe arena, just outside of Tokyo.

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