Chicago greeted festival-goers with sporadic, vicious thunderstorms before they got the chance to enter Union Park, almost like a divine test of will for the sheer spectatle that awaited.
Zach Medearis of Outer Minds resembled a Guitar Hero character, but played like a '60s legend.
Jana Hunter of Lower Dens expertly juggled Korg and guitar duties, while sporting a shirt from Hunter S. Thompson's closet.
Willis Earl Beal strutted the stage with a soulful, manic ferocity, likely the reason for his Jack & Coke spilling.
After a slew of hype men from his mob revved up the already feverishly-excited crowd, A$AP Rocky emerged to a roaring assemblage of blunts and screaming 20-year-olds, only to bring the rain later in the set.
Brian King of Japandroids, dressed a little like Springsteen circa-1980s, was extremely fastidious about the sound levels emanating from his armada of Marshall amps after the rain.
Clams Casino, whose official website is still SoundCloud, threw down a riveting mix of Texan-sizzurp sludge beats, and delirious samples.
David Longstreth, a fitting name for the gangly lead singer of Dirty Projectors, straining for the higher notes.
Megan James of Purity Ring keeping the beat in front of the band's largest crowd to date.
Feist ended the day with a soothing, controlled blend of delicate audience-involved melodies, complemented by a trio of cloaked female back-up singers who resembled a nicer version of the characters from Hocus Pocus.