Mac Miller recently joined Prodigy and Alchemist during their visit to DJ Tony Touch on Toca Tuesdays and spit a freestyle with the other two. Yes Alchemist actually spits some bars in this.

Schoolboy Q Reviews Mac Miller's "Watching Movies With The Sound Off" Album
Doe B Ft. T.I., Birdman & Young Dro - Kemosabe (Remix) (Behind The Scenes)