UPDATE: The official Lolla aftershows have been revealed and they boast an impressive assortment of performers: We're talking Alabama Shakes, Passion Pit, Dr. Dog, Frank Ocean, Calvin Harris, Tune-Yards, the Afghan Whigs and plenty more. Check those out over here.

The 2012 Lollapalooza lineup has been announced! And it is undeniably epic thanks to these two words: Black Sabbath. The Chicago music festival snagged the reunited metal pioneers for their only North American concert date so far. It really doesn't get much better than that.

Oh wait, it does: Red Hot Chili Peppers are also headlining the fest, along with Jack White, Florence + the Machine, The Black Keys and the recently reunited post-hardcore outfit At the Drive-In.

Electronic acts Avicci, Bassnectar, Justice and Miike Snow are slated to move the crowds in Grant Park along with rapper J. Cole. The tantalizing list of indie artists includes The Shins, Fun., Sigur Rós, Passion Pit, Franz Ferdinand, and The Afghan Whigs' first show on U.S. soil since reuniting. R&B's two most promising newcomers—Frank Ocean and The Weeknd—will also represent at the August 3-5 fest.

Three-day passes are on sale at now www.Lollapalooza.com, and considering Lolla's early bird passes sold out within minutes on March 27, you might want to grab those soon. A limited number of single day passes will go on sale later this summer.

Check out the full lineup over at Lollapalooza's website and don't miss our definitive 112 track Lollapalooza Spotify playlist. Which acts you're most excited to see below. Sabbath? Peppers? Solo Jack White? Florence? It's hard to say, which is a very good thing for anyone who scores a ticket.