Solange Knowles was in the middle of her set and without warning, the 32-year-old R&B singer walked out on stage. The curly-haired sibling duo then treated the crowd to a lively and choreographed version of "Losing You."
Bey donned a summery lavender fruit-patterned top with a matching skirt and a black hat, while Solange opted for Max Mara's Spring 2014 red-orange three-quarter sleeve leather jacket and romper. The sisters shared a sweet embrace at the end of Bey's special appearance.
Hov, who headlined the music and arts festival four years ago, took the stage with his former nemesis, Nas. The rappers performed "Dead Presidents II" and "Where I'm From." Sean "Diddy" Combs also joined Nas for "Hate Me Now," his last song of the concert.
To celebrate the 20th anniversary of his debut release, Nas performed his entire Illmatic album.
Pharrell Williams' appearance featured some very special guests, including Nelly doing "Hot in Herre," Busta Rhymes and Diddy crooning "Pass The Courvoisier Pt. 2" and Snoop Dogg rapping "Drop It Like It's Hot" and "Beautiful."
Stefani, who welcomed her third son in March, did a rousing version of "Hollaback Girl." The rocker donned a custom Spring 2014 L.A.M.B. jumpsuit.
17-year-old newcomer Lorde also performed.