There’s a reason why Eminem is credited as being one of hip-hop’s most prolific lyricists. It’s because he is. Marshall Mathers delivers on every track he approaches—whether it’s his or someone else’s. He has a knack for switching up his style to fit anything he sonically steps into, turning hum-drum tracks into bangers and morphing stand-out songs into classic. He's a formalist at heart, always looking for new ways to wrap his words around a particularly challenging beat. He'll steal a song right from under you if you're not careful.

While we anxiously await Eminem’s upcoming Marshall Mathers LP 2, XXL has compiled some of Em’s best guest verses, from the super mainstream to the more obscure. Truth be told, it’s hard to find the best of the best in the midst of Em’s whole catalog, but we’ve pulled 15. Check them out.