Lorde and Addison Rae join Charli XCX onstage at Madison Square Garden Sweat Tour stop

Lorde thrilled fans when she made an unexpected appearance at Charli XCX's Sweat tour stop at Madison Square Garden in New York City on Monday night. 

The two artists teamed up for a live performance of their remix, "Girl, So Confusing," marking the first time they had performed the track together in front of a live audience.

In another exciting twist, Addison Rae took to the stage alongside Charli and Troye Sivan for a debut performance of her song, "Diet Pepsi." 

She also joined Charli for a live version of the "Von Dutch" remix, where Rae was featured on the track.

Charli and Troye kicked off their Sweat tour in Detroit on September 14 and are set to continue electrifying audiences, with Philadelphia being their next stop on September 25. 

This tour has already become a fan favorite, with unexpected collaborations like these keeping the excitement alive at each show.