(CNN) -- "Are y'all alive?" Andre 3000 probed the first-day Coachella goers as he took the stage with Big Boi in the first of their reunion shows.
The duo, who haven't performed together since their 2006 Idlewild album, hooked the crowd as they opened with their Stankonia hit "B.O.B." ("Bombs Over Baghdad"), before going into a rapid-fire of "Gasoline Dreams," "ATLiens," "Skew It on the Bar-B" and "Rosa Parks." Andre 3000 then told the crowd it feels so good to be back, as he talked about the 20-year anniversary of Outkast (they formed when they were in high school in 1992 and released their debut album in 1994).
A notable legend was there to witness the first of their many reunion shows. Andre told the crowd that "one of his idols" -- the Purple One, Prince -- was backstage watching as they also ran through "SpottieOttieDopaliscious," "Roses" and "Elevators."
In the middle of the set, Big Boi and Andre both took time to showcase some of their solo work from their double album, "Speakerboxxx/The Love Below," before rapper Future and Janelle Monae also made appearances.
"This is my favorite group in the entire world," proclaimed Monae. "And what we're witnessing tonight is history."
Outkast's run of mainstream hits came at the end of their set as they went from "Ms. Jackson" to "So Fresh, So Clean," "The Way You Move" and "Hey Ya!" They then tried to squeeze in an encore song with Killer Mike, but weren't able to perform it before the festival's 1 a.m. cutoff.
Earlier in the day, Grouplove, Ellie Goulding, Chromeo and Girl Talk were among the acts that prepped the main stage before Outkast. Grouplove got the crowd dancing to tracks off their latest album "Spreading Rumours," before Ellie Goulding really got fans fired up with her sunset set, drawing celebrities including Selena Gomez, Kendall and Kylie Jenner and Joe Jonas to the front for the Brit's high-energy performance. The Top-40 mainstay powered through her list of electro-pop hits like "Lights" and "I Need Your Love," before getting everyone to their feet with closer "Burn."
Chromeo got the masses moving with their disco-flavored electro-funk. Although they are Coachella vets, this weekend brought them a few festival firsts -- playing on a Friday and performing on the main stage, which they told CNN they found to be more challenging to connect with the crowd.
"On the big stage, they're 50 feet away, so I could barely hear them," said guitarist and lead singer Dave 1 after their set. The duo ran through a mixture of familiar hits, including "Fancy Footwork" and "Momma's Boy," as well as tracks from their forthcoming album, "White Women." Toro Y Moi made a guest appearance for recent single, "Come Alive."
Other Day 1 crowd-pleasers included Aloe Blacc, Bastille (who garnered a crowd that waited through their entire set to hear the familiar hit song "Pompeii"), Broken Bells and HAIM. The sister act performed on the Outdoor Theatre during the peak of the heat in the afternoon. In between her now-notable "bassface" expressions, Este Haim told the crowd that she has been coming to Coachella since 2004, but that this is the first year she hasn't had to run through a rose bush or hop a fence to get inside.
Meanwhile in the Sahara tent, newcomer Martin Garrix attracted a crowd that extended past the tent walls as he opened his set with his notable track "Animals." His mix included samples from other Coachella weekend acts like Kid Cudi and Krewella, which had the crowd yelling along to the lyrics. But the most impressive part of the 17-year-old's hour-set was the striking laser-light show that prompted the majority of the tent to take out their cell phones and capture it on video.
Mainstream DJ/producer Zedd continued the fist-pumping/sing-along combination next as he played his radio hits like "Stay the Night" and "Clarity." The 24-year-old's set got the stamp of approval from Oscar winner Jared Leto who Instagrammed a photo from the stage writing "My friend @Zedd destroying #coachella."
With two more days ahead in Indio, California, Chromeo's Dave 1 summed up the festival's continued attraction calling it "the most indie-centric music curation" with mainstream appeal.
"It's the festival where you have the coolest bands that get the biggest looks," he said. "Coachella's got a sexiness to it that no other festival in the world has."