The 32-year-old singer and 47-year-old rapper took to the stage at the annual awards show in Los Angeles.
Ciara and Elliott delivered an energetic rendition of Ciara's song "Level Up (Remix)." The pair were joined by a group of backup dancers and drumline performers.
"Fireworks, dancers and a drumline?! That #AMAs performance from @ciara and @MissyElliot was on another LEVEL," the AMAs wrote on its official Twitter.
Elliott expressed her gratitude in a tweet prior to the awards show.
"Thank you @AMAs & @ciara for having me I'm humbly grateful & never take for granted the love shown from all my fans thank all of you," she wrote.
Ciara shared a behind-the-scenes photo earlier in the day during rehearsals with Elliott.
"Selfies With My Sis Miss. @MissyMisDemeanorElliot @AMAs Rehearsals Special Moments #LevelUp #Dose," she captioned the picture on Instagram.
Ciara released "Level Up (Remix)" with Elliott and Fatman Scoop in July. She and Elliott have collaborated on several other singles, including "Lose Control," "1, 2 Step" and "Work."
The original "Level Up" will appear on Ciara's forthcoming seventh studio album. The singer last released the album Jackie in 2015, and has debuted three singles, "Level Up," "Freak Me" featuring Tenko and "Dose," this year.
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