The element of surprise is one of the many things that make Bizarrap‘s music and freestyle sessions some of the most watched videos on YouTube. Who will his next guest be? No one really knows, but when the Argentine producer drops a new session, it gets millions of views in a matter of hours.

His music session with the Spaniard Quevedo is among his most watched, and it’s the one that has catapulted him to global success. Their “Bzrp Music Sessions, Vol. 52” scored both their first entry on the Billboard Hot 100. Currently, it has more than 400 million views on YouTube. Additionally, the track is only the second fully Spanish-language song to top the Global 200 in the chart’s two-year history, following Bad Bunny and Jhay Cortez’s “Dákiti” in 2020.

“The first ‘session’ back in 2018 wasn’t even planned,” Biza previously told Billboard. “All I wanted to do was record a local rapper who goes by Kodigo and upload that to YouTube because I was a big fan of his and I wanted others to listen to him too. My plan was to record with my phone, but for some reason it didn’t work. So we scheduled the session for the following day and I thought, ‘Why not give these freestylers the production they deserve with microphones and everything?’ So that’s what I did.”

Since then, he’s recorded freestyle and/or music sessions with Nicki Nicole, Nicky Jam, Nathy Peluso, Cazzu and Residente, among many others. Most recently, he tapped Shakira for his “BZRP: Music Sessions #53.” In the surprise track, the Colombian star doesn’t hold back and is as blunt as ever about her ex, Spanish soccer star Gerard Piqué. “A she-wolf like me doesn’t have time for novices like you/ I was too much for you, that’s why you’re now with someone more like yourself,” she sings over a futuristic pop-electronica beat. 

Below, Billboard ranks 13 of Bizarrap’s sessions.