'AGT' judges Simon Cowell, Howie Mandel get 'deepfake' treatment by AI act Metaphysic: Watch here

“America’s Got Talent” was a rollercoaster of eclectic talent Tuesday night, and even the judges were reeling from the unpredictable variety.

Eleven more acts graced “the greatest stage in the world” for a chance at a spot in the “AGT” finale. Simon Cowell dubbed one act’s performance “the best act of the series,” while Howie Mandel compared another act to a “school assembly” performance.

Some contestants found a way to stand out from the pack. Golden Buzzer singer Lily Meola moved the judges with an emotional performance of an original song, while comedian Mike E. Winfield’s hilarious set prompted Cowell to predict his place in the finale.

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Here are the highlights from the live show.

Bayley Graham

New Zealand tap dancer Bayley Graham offered an agile performance set to Ed Sheeran’s “Shape of You.” Graham’s percussive dance steps electrified the stage, as well as the glowing staircase he moved on and off of with ease.

Heidi Klum commended Graham’s “great charisma” and “great showmanship.”

“Any Broadway stage and any Vegas stage should be lucky to have you,” Klum added.

Mandel said Graham is bringing back the dancing prowess of icons Fred Astaire and Gene Kelly for a younger generation. “This stage is lucky to have you,” he said.

But Cowell said he found Graham’s performance “slightly underwhelming,” adding that it lacked "a spectacular ending.”

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Acapop!

Acapella youth group Acapop! delivered a heartwarming performance of an original song, but the judges weren’t in harmony with how they felt about it.

“I felt like I was at a school assembly,” said Mandel, who gave the group a red ‘X.’ “It just doesn’t rise to the level of ‘AGT’ in my mind.”

Sofía Vergara said while she thought the group’s audition was stronger than their performance, she praised their stripped-down vocals and song choice. “I have to remind myself that you guys are singing without instruments: It’s only your voices,” Vergara said. “You guys did a very good job, and it’s a risk to use an original song.”

Cowell said even though the group’s song wasn’t “great,” the singers’ vocals are top-notch and encouraged them to embrace their individuality.

“Your raw talent is unbelievable,” Cowell added. “If you do get a chance to perform again, I would do an incredible cover version in your style, wear your own clothes, have fun and be who you are because you’re hugely talented.”

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Jannick Holste

German dancing magician Jannick Holste gave an eye-popping performance, fusing his spirited footwork with mind-boggling illusions.

“You really are everything,” Klum told Holste.

However, Cowell said the 20-year-old’s “horrible” dancing diminished the quality of his performance.

But Vergara was left astounded by Holste’s performance.

“I don’t know what goes on when he gets on that stage,” Vergara said. “Is it bad? Is it good? I don’t even know, but I enjoy it.”

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Lee Collinson

British singer Lee Collinson slowed things down with a soaring rendition of “Flowers” by Lauren Spencer-Smith.

But in true Cowell fashion, he was not impressed with Collinson’s choice of song.

“It didn’t sound like it was the right key for you. It actually sounded like you were reading a letter,” Cowell said. “You’ve got a good voice…but I don’t think you got it right tonight.”

Mandel agreed. “You picked a song that had absolutely no range,” he said. “If I was listening to that on the radio, I would’ve turned the channel because the song bored me, not you.”

But Klum said Collinson’s vocal delivery brought something “different.”

“Your voice is sweet, it’s pure. It’s not as polished maybe as some of the singers are,” Klum said. “It's sweet to hear your English accent creep in every now and then.”

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Jack Williams

Ventriloquist Jack Williams did double duty on Tuesday, alternating between the voices of his “new best friend” Dale, a one-toothed orange puppet, and his former “partner” Foster the bunny. Williams also threw in impersonations of judge Cowell and former President Barack Obama.

Cowell gave Williams a standing ovation and called his performance “the best act by a mile tonight.”

“It was really clever (and) the way you staged everything was funny,” Cowell said.

Klum appreciated the addition of the Cowell and Obama impersonations. “It was a little bit hard to differentiate your voices and your two friends,” she said. “So, I like that you added two extra other voices in there.”

Mandel criticized the lack of originality in Williams’ performance. “I wasn’t blown away, but I think you’re really good and hopefully America loves you,” he said.

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Metaphysic

AI musicians Metaphysic bent reality once more, delivering a stunning operatic performance using AI projections of Cowell, Mandel and host Terry Crews.

The group brought all the judges to their feet, with Cowell calling the performance “the best act of the series.”

“The fact that you had the gumption to actually use my own voice is amazing,” said Mandel of the "deepfake" jokingly. “It’s like Il Divo, but it’s Il Stupido.”

Klum was floored by the group’s integration of music and technology.

“Beautiful singing, the opera was amazing,” Klum said. “And then when you swap the faces live right here, the whole thing is epic.”

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The Lazy Generation

Stunt group The Lazy Generation struck a perfect balance of captivation and cringeworthiness.

Dressed in baby pink tutus, the self-described group of “professional idiots” performed a series of zany stunts, including a game of cactus tug-of-war, which saw the group playing tug-of-war over a garden of prickly cacti.

“I don’t know if you should be encouraging this kind of stuff, but at the same time, I have to say I could not look away,” Klum said.

Cowell thought the performance was a notable improvement for the group. “It was a step up from the first audition,” he said. “This is not to everyone’s liking, however, it’s different.”

But Vergara couldn’t get on board and gave them a red ‘X.’

“I feel it’s unnecessary pain,” Vergara said. “My husband loved it and my son loved it during the audition, but it’s not something I want to see ever again.”

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Merissa Beddows

Vocal impersonator Merissa Beddows used her performance to pay tribute to the female voices that inspired her craft, seamlessly transitioning between impersonations of Celine Dion, Cher and Amy Lee of Evanescence.

Vergara said Beddow’s impersonations were “so spectacular.”

Cowell said while Beddows’ performance was better than her audition, her video intro lacked personality.

“I still don’t know who you are,” Cowell said. “ ‘Cause I think you’re funny, but for some reason, we don’t know you properly.”

Klum was impressed by Beddow’s versatility. “You’re a woman of many different talents, and I love watching you,” she said.

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Harper

Death metal singer Harper performed a hair-raising cover of Ed Sheeran’s “Bad Habits,” interweaving spoken-word verses with ferocious vocals.

“Death metal is maybe not my personal favorite music, but it is fascinating watching you,” Klum said,

Vergara said Harper’s effortless vocal delivery is “disturbing” — in a good way.

“Even without the element of surprise this time, the way she surprised us in the audition, it was amazing,” Vergara said.

Cowell called the young vocalist “gutsy” and commended her for her originality.

“I love things people are going to talk about,” Cowell said. “This is something we don’t normally see or hear.”

Mike E. Winfield

Comedian Mike E. Winfield charmed the judges – and the studio audience – with his down-to-earth humor.

“Your jokes are so relatable,” Vergara said. “I hope that people vote for you tonight because you were amazing.”

Klum said Winfield is the total package.

“You’re good-looking, you have the swagger going on, you’re funny,” Klum said. “No comedian has made it yet to the big finale, so maybe this one is going to be you.”

Cowell praised the comedian’s onstage charisma.

“It was a star performance,” Cowell said. “I think America is going to put you through to the finals after that.”

Lily Meola

Singer Lily Meola, who received the Golden Buzzer from Klum during her audition, offered up a tender performance of her original song “Butterfly.”

“You have the most beautiful voice. It’s soaring through the room,” Klum said. “You are incredible.”

Cowell said Meola made the right call performing an original song.

“People are going to remember it. The lyric was beautiful,” Cowell said.

Vergara agreed. “It’s very emotional every time you come to that stage,” she said. “I congratulate you for writing that song.”

This article originally appeared on USA TODAY: 'AGT': Simon Cowell praises AI opera as 'best act of the series'