9 Unforgettable Moments from the 2018 Billboard Music Awards

Here are the performances, speeches and outfits that dominated Sunday's BBMAs.

The Billboard Music Awards rocked the MGM Grand Garden Arena in Las Vegas on Sunday, and almost all the biggest names in music and entertainment came out to celebrate the artists, songs, and albums that took the world by storm this year.

In a night filled with bombastic live performances and emotional, touching speeches, there were a few moments that stood out from the rest.

Here are some of the biggest, best and most important highlights from Sunday's BBMAs.

1. Emotional Tribute to Santa Fe High School Shooting Victims

Kelly Clarkson somberly opened this year's show with an emotional call to action in response to the mass shooting at Santa Fe High School in Texas on Friday. The 36-year-old singer fought back tears from the first moment of her powerful speech, where she rejected the idea of having a moment of silence in favor of calling for a "moment of action [and] a moment of change."

The tragic shooting, which is believed to have been committed by a 17-year-old student who attended the high school, claimed the lives of 10 people, eight children and two adult teachers, and left 13 others wounded.

"Mommies and daddies should be able to send their kids to school, to church, to movie theaters, to clubs. You should be able to live your life without that kind of fear," Clarkson said "We need to do better. Because we're failing our children, we're failing our communities and we're failing their families. I have four children; I cannot imagine getting that phone call or that knock on the door."

2. Ariana Grande Kicks Things Off With a Splash

The 24-year-old singer kicked off the awards show with a rain-soaked, umbrella filled performance of her new single "No Tears Left to Cry," while rocking a black babydoll dress and thigh-high leather boots.

The appearance marked Grande's first televised performance since her split from longtime boyfriend Mac Miller earlier this month, and it's clear the singer hasn't let it affect her stage presence. Grande didn't miss a beat during the stylish number, which was a beautiful live recreation of the song's psychedelic music video.

3. Kelly Clarkson Proves Why She's the Best Choice to Host

When Clarkson took the stage for her opening monologue, the singer showed exactly why she was the best possible choice to host: her effortless enthusiasm and genuine appreciation for her fellow artists.

After saying she was going to keep things "simple" as the evening's host, Clarkson immediately kicked into an over-the-top medley of some of the nominated artist's biggest hits, including Maren Morris' "My Church," Sam Smith's "Too Good at Goodbyes," and Kendrick Lamar's "Humble." 

Clarkson continued with her cover of Imagine Dragons "Thunder" and Khalid's "Young Dumb & Broke" -- which Khalid himself couldn’t help but dance to in the audience -- and then performed Cardi B's verse from Bruno Mars' "Finesse" as well as Ed Sheeran's "Shape of You," Shawn Mendes' "Nothing Holding Me Back" and Taylor Swift's "Look What You Made Me Do."

As the explosive, acrobat-filed display of extravagance came to a close, Clarkson jokingly reiterated that she planned on "keeping it simple."

Later in the evening, Clarkson stepped back from hosting for a live performance of her own music.

The singer took the stage in a golden, fringe-covered dress to belt out a rendition of "Whole Lotta Woman," off her 2017 album The Meaning of Life.

4. The Chainsmokers Honor Avicii

Before presenting the award for Top Hot 100 Song, The Chainsmokers' Andrew Taggart and Alex Pall joined Halsey to pay tribute to the late EDM artist Avicii.

"His passing was a great loss for the music world, and for us," Pall shared, somberly. "He was an artist who inspired so many and in so many ways. And, simply put, he meant so much to us and everyone in the EDM community."

"Everyone who worked with him would agree that he was such a joy," Halsey added. "And it makes this tragedy all the more painful."

Not long after paying tribute to the late artist, The Chainsmokers took home the award for Top Dance/Electronic Artist, and Pall dedicated the Golden Microphone to Avicii and addressed the artist's influence on EDM and pop.

"We want to dedicate this award to Avicii. None of us would be here. Everyone who was nominated for this award was massively influenced by him," Pall shared, in part. "He will be missed."

5. Demi Lovato and Christina Aguilera Belt Out Wild Duet

There's no denying that Lovato and Aguilera stole the spotlight with their insane diva-off when the pair took the stage to perform their girl-power duet "Fall in Line." 

Rocking matching black leather trench coats, the amazing number seemed to be set in a dystopian police state, with back-up dancers in fascist-like black uniforms and militaristic helmets. It gave the whole thing an emotional Handmaid's Tale/1984 vibe that really added some emotional weight to the defiant, feminist messages and themes of the powerful song.

6. BTS Has the Absolute Best Night

Every time BTS was mentioned, or the cameras cut to them in the audience, everyone freaked the hell out. Every. Single. Time. So you can only imagine how loud things got when the seven K-pop megastars took the stage to perform their song "Fake Love."

Kelly Clarkson came prepared while introducing the band, bringing out some fuzzy pink earmuffs to defend her ears against the deafening roar of the fans. 

RM, J-Hope, Jin, Jimin, Jungkook, Suga and V slayed the flawless performance with their signature intricate stage presence and complex dance moves that put most of the night's other live numbers to shame.

Before their acclaimed performance, the bandmates also took home the award for Top Social Artist for the second year in a row, after becoming the first Korean artists to ever take home a Billboard Music Award in 2017.

7. An Emotional Musical Call For Gun Control

The BBMAs addressed the Santa Fe High School shooting once again during the show with an impassioned call for gun control via a performance by Shawn Mendes and Khalid of their emotional ballad "Youth." 

The two stars were joined by the choir of Marjory Stoneman Douglas High School in Parkland, Florida, where 17 people were killed and 17 others injured in a mass shooting that left the nation devastated. 

8. Janet Jackson Gets Real

The legendary pop superstar was honored with the BBMAs' Icon Award  -- presented by surprise guest Bruno Mars -- making Jackson only the seventh artist -- and first black woman -- to receive the award.

To celebrate the honor, Jackson performed a medley of some of her biggest hits -- including "Nasty" and "Throb" -- in her first live, televised performance in many years.

While her musical presence drew a standing ovation, Jackson really blew people away with her powerful acceptance speech in which she said Americans are living "in a glorious moment in history."

"It's a moment when, at long last, women have made it clear that we will no longer be controlled, manipulated or abused," Jackson said. "I stand with those women, and with those men equally outraged by discrimination who support us. This is also a moment when your public discourse is loud and harsh."

9. Salt-N-Pepa Close Out the Show With Classics

The awards show closed out the night with some serious girl power with Hip-hop icons Salt-N-Pepa, who performed a selection of their greatest hits, including "Shoop," "Let's Talk About Sex" and "Push It."

However, things became next-level epic when En Vouge came out to perform with Salt-N-Pepa for their 1994 super-hit "Whatta Man," which brought the entire audience to their feet to sing along.

Check out the video below for a look at the most memorable moments from last year's Billboard Music Awards.