BEyonce & Bruno Mars - LEAD
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Every superhero has their weakness, and we now officially know what Beyoncé’s kryptonite is.

Bruno Mars is the latest star to open up with a treasure trove of information about what Queen Bey is like when the cameras aren’t rolling. In an interview with Rolling Stone, the popular singer spills on his epic 2015 Super Bowl halftime trio performance with Coldplay and the Lemonade singer, explaining that he wasn’t totally convinced to join until Beyoncé came on board.

After Coldplay front man Chris Martin met with Mars in person and suggested he team up with the beauty on "Uptown Funk," the duo took a video together and sent it straight to Beyoncé’s cell phone. “Let’s talk to her right now!” Martin reportedly told Mars while he remained skeptical of the idea.

The rest, as they say, is history, but there’s one fun incident that caught Mars by surprise in the rehearsals leading up to their joint performance. “She’s not f*****g joking around,” Mars said of her talent. “She’s going to get on stage and show everybody why she’s the best every single time. She’s got that monster in her.”

A monstrous need to slay obviously fuels Beyoncé, but she also relies on one go-to snack. “Me and Beyoncé were both working on our diets, stressing out,” he said, adding, “Then the day before, we’re watching playback backstage, and she’s eating a bag of Cheetos. I’m like, ‘That’s what you’re doing?’”

Not surprisingly, she kept it real. “She’s like, ‘There’s nothing more we can do these last two days. It’s gonna be what it’s gonna be. So I’m gonna enjoy this bag of Cheetos.”

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Truer words have never been spoken.