A mass of hard-hitting rock bands took to the Chilean installment of Lollapalooza 2013, boasting brilliant performances and insane jam sessions. Not only did Pearl Jam and Queens of the Stone Age deliver full sets, but members of each act joined their respective counterparts for some Pearl / Queens collaborations in front of the 70,000-person crowd.

Along with stellar sets from monster acts such as the Black Keys, A Perfect Circle, Puscifer and the Hives, Queens of the Stone Age performed a 16-song set consisting of 'No One Knows,' 'Go With the Flow,' new track 'My God is the Sun' and many more cuts. Perhaps most notably, however, Queens of the Stone Age invited Pearl Jam's Eddie Vedder onstage to provide backup vocals and essential cowbell percussion for 'Little Sister.' Forgive us for making the world's billionth joke on this, but in our opinion, what does 'Little Sister' need? More cowbell! Thankfully, Vedder did the instrument justice.

Pearl Jam tore through their classics-packed setlist for the giant Chilean audience, including staples such as 'Jeremy,' 'Even Flow' and 'Yellow Ledbetter,' along with covers of the Dead Boys staple 'Sonic Reducer' and Neil Young's 'Rockin' in the Free World,' the latter of which saw guest appearances by Queens of the Stone Age's Josh Homme and Jane's Addiction singer / Lollapalooza mastermind Perry Farrell. The group performance, which was accompanied by jaw-dropping fireworks electrified the entire crowd from front to back, as evidenced in some fan-filmed footage posted below.

Check out both Queens of the Stone Age's performance of 'Little Sister' and Pearl Jam's rendition of 'Rockin' in the Free World' from Lollapalooza Chile below!

Queens of the Stone Age, 'Little Sister' with Eddie Vedder

Pearl Jam, 'Rockin' in the Free World' with Josh Homme and Perry Farrell

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