The initial lineups for the annual Riot Fest shows in Chicago, Denver and Toronto were announced last month. Now the festivals have revealed a second wave of artists that will be playing.

Added to the Denver Riot Fest are System of a Down, The Prodigy, Death Grips, 88 Fingers Louie, Chef’Special, and Input & Broken. The event will be held August 28-30 at National Western Complex. Previously announced bands include Motorhead, Anthrax, Modest Mouse, Iggy PopRancidTestamentGWAR and the Pixies.

The Chicago Riot Fest will be Sept. 11-13 in Douglas Park, and newly added bands include System of a Down, The Prodigy, 88 Fingers Louie, and Chef’Special. Also playing in Chicago will be Faith No More, Motorhead, Tenacious D, Coheed and Cambria, GWAR and Against Me!

The second wave of announced bands for the Toronto Riot Fest includes Weezer, who will be playing their entire Pinkerton and The Blue Album records. The Prodigy, Cancer Bats, Bleachers, Courage My Love and Ritual will also rock the Toronto Riot Fest Sept. 19-20 at Downsview Park. They join previously announced bands Rancid, Motorhead, Thrice, All Time Low, Alexisonfire and Wu-Tang Clan.

For all the details on the three Riot Fests, including ticket info, go to the festival's official website. Check out the posters below for the complete Chicago, Denver and Toronto Riot Fest lineups.

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