Three songs into his four-song set at the iHeartRadio Music Festival’s Daytime Village in Las Vegas on Saturday afternoon (Sept. 23), One Direction star Niall Horan took a moment to acknowledge radio listeners with the news that his second single, “Slow Hands,” had reached the top of charts, showing no sign of, er, slowing down. “I’m very proud to be a part of this lineup,” Horan told the crowd. “It’s been an unbelievable summer for me. Thank you guys for listening to the radio and asking for the song. I really appreciate it.”

A diverse lineup of artists took the stage at the Daytime Village, each of whom have radio at least partly to thank for launching their careers. Highlights included red-hot sets by Halsey, Bleachers, Kelsea Ballerini, Migos, Khalid, Bebe Rexha (with a surprise appearance by Louis Tomlinson for their hit, “Back to You”), French Montana (with surprise guest Juicy J), Noah Cyrus, Little Mix, All Time Low, Hey Violet, and Cheat Codes.

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Other standout moments included a hot set by Halsey, who kicked off her performance with “Strangers,” her collaboration with Fifth Harmony’s Lauren Jaregui, and continued with her hit, “Now or Never” and her Chainsmokers’ collaboration, “Closer,” with “my part, because it’s better,” she cracked. Halsey later promised the Vegas crowd that she’ll return for an all-ages New Year’s Eve show to make up for a recently cancelled date.

Khalid lit up the stage with a smile and a tight band as the young audience sang every word of his set, including the show closer “Young, Dumb and Broke.” Bleachers also worked the crowd into a sweaty frenzy as singer Jack Antonoff demanded fans get on their friends shoulders so it would, “Feel more like a festival.” The band amped things up with the Springsteen-esque “Rollercoaster” and anthemic “I Want to Get Better.”

Little Mix caused a commotion with an a capella rendition of their song “Wings.” Unfortunately, member Perrie Edwards —or  “our little Periwinkle,” as Jade Thrilwall billed her — was “under the weather” and unable to group her groupmates.

The excitement of the day crackled onstage and off. Simon Cowell discovery PrettyMuch introduced Bebe Rexha  with a brief song and ABC “Boy Band” winners In Real Life — on hand to welcome All Time Low — all mingled backstage, getting handshakes and guidance from seasoned vets Horan and Tomlinson.

Bebe Rexha, Louis Tomlinson. Bebe Rexha, left, and Louis Tomlinson perform at the 2017 iHeartRadio Music Festival Day 2 held at T-Mobile Arena, in Las Vegas 2017 iHeartRadio Music Festival - Day 2, Las Vegas, USA - 23 Sep 2017

“Bachelor” Nation was thrilled by the appearance of Ben Higgins, Dean Ungert (whose podcast, “Help! I Suck at Dating,” is being promoted by iHeart) and Peter Kraus. Higgins arrived shortly after Cyrus, just missing his moment in the spotlight as she declared her love for the star and dedicated her song, “I’m Stuck,” to him from the stage. The other stars of the festival? Puppies. Every performer stopped in to check out the puppy adoptions in the backstage area —including Cyrus, the Impractical Jokers and Casey Moreta from Hey Violet, who all took home a precious pooch.

Indeed, it was a Cyrus family affair at the show, with sister Noah performing earlier in the day and Brandy delivering a guitar to Miley onstage later, when Cyrus played a potent set of hits that included “Malibu,” “We Can’t Stop,” a cover of Nancy Sinatra’s “These Boots are Made for Walking” and an incredible reinventing of the song “Party in the USA” with messages on the screen touting education, equality, opportunity, and even healthcare.

Miley Cyrus performs at the 2017 iHeartRadio Music Festival Day 2 held at T-Mobile Arena, in Las Vegas 2017 iHeartRadio Music Festival - Day 2, Las Vegas, USA - 23 Sep 2017

“It’s not a party in the USA if we don’t have equality, justice, understanding, change, expression kindness, opportunity [and] I won’t stop fighting for justice for every f—ing single one of you,” she said — one of 12 F-bombs she dropped during her 25-minute performance.

Backstage, Cyrus told syndicated radio host Elvis Duran that she wants to influence fans to “stand up to discrimination,” and made the song “more of a message for people.”

Referencing her infamous Video Music Awards appearance with Robin Thicke in 2014 “when everyone was me for Halloween,” she said she would rather have a positive social impact in these times. “If people are going to talk about me I want them to have something to say,” she added.

Big Sean performs at the 2017 iHeartRadio Music Festival Day 2 held at T-Mobile Arena, in Las Vegas 2017 iHeartRadio Music Festival - Day 2, Las Vegas, USA - 23 Sep 2017

The music continued into the night at the T-Mobile Arena with high wattage bows by Kesha, Miley Cyrus (in thigh-high “walking”-ready boots, Kings of Leon, Lorde, Big Sean (the MVP of the night, who flew in from the Global Citizen Festival in New York to keep the party going and “end my night right here in Vegas”), Thomas Rhett, Tomlinson and Horan, and DJ Khaled, who loaded his set with surprise appearances by Chance the Rapper; Travis Scott (recently announced pregnant girlfriend Kylie Jenner supported from backstage), for “Butterfly Effect” and “Goosebumps;” French Montana on “Unforgettable;” and Demi Lovato, who hopped onstage for “Sorry, Not Sorry.”

Quavo, French Montana, DJ Khaled, Travis Scott. Quavo, from left, French Montana, DJ Khaled and Travis Scott perform at the 2017 iHeartRadio Music Festival Day 2 held at T-Mobile Arena, in Las Vegas 2017 iHeartRadio Music Festival - Day 2, Las Vegas, USA - 23 Sep 2017

Other surprise appearances included Macklemore, who joined Kesha onstage at the T-Mobile arena for their brand new collaboration “Good Old Days.” The singer then took an emotional turn with her hit, “Praying.” Fellow Nashville natives Kings of Leon, meanwhile, represented for the rock format, opening their set with “Use Somebody” and killer versions of “Sex on Fire” and “Waste a Moment.”

Kesha performs at the 2017 iHeartRadio Music Festival Day 2 held at T-Mobile Arena, in Las Vegas 2017 iHeartRadio Music Festival - Day 2, Las Vegas, USA - 23 Sep 2017

Self-described “young goth” Lorde, introduced by actor Taylor Lautner, who promptly went straight out into the audience to groove to her set, lamented that she wasn’t old enough to gamble in Sin City, but delivered a grown up and explosive show that had two surprise performers: rising star Khalid on “Homemade Dynamite” and producer Jack Antonoff who sat at the piano to perform “Liability,” a song they wrote together.

Khalid, Lorde. Khalid, left, and Lorde perform at the 2017 iHeartRadio Music Festival Day 2 held at T-Mobile Arena, in Las Vegas 2017 iHeartRadio Music Festival - Day 2, Las Vegas, USA - 23 Sep 2017

Country star Thomas Rhett represented the genre beautifully with his ’50s-inspired “Crash and Burn,” the Maren Morris duet “Craving You,” and gorgeous “Die a Happy Man.” Rhett also gave props to Lorde, declaring that the 20-year old New Zealand star “blew my mind tonight.”

Thomas Rhett performs at the 2017 iHeartRadio Music Festival Day 2 held at T-Mobile Arena, in Las Vegas 2017 iHeartRadio Music Festival - Day 2, Las Vegas, USA - 23 Sep 2017

If anything, Rhett represented all that the iHeart Festival is all about. Primarily a country star, Rhett plugged Big Sean’s forthcoming set and snuck in a little bit of Bruno Mars “That’s What I Like” into his current song, “Unforgettable.” It is this spirit, iHeartRadio morning show host Elvis Duran told Variety, that makes the show so unique. And the positive vibes often extend beyond the two-day concert. For instance, Chris Stapleton and DJ Khaled bonded backstage and ended up discussing future collaborations.

“The Weeknd, Pink, Harry Styles, Lorde, Miley Cyrus, Niall Horan, Kesha — [these are] artists I have known since they started,” said Duran. “They are like my kids, so to watch them turn into these superstars is just amazing.” Certainly this Las Vegas audience couldn’t agree more.