Criminally underrated and overlooked as a producer. He was an extremely talented artist in his heyday and he definitely deserves far more recognition than he gets, but I think his whole Humpty Hump persona sort of overshadows all his production.
He would probably be in my Top 5 producers 2Pac ever used, I mean the work they done together was impeccable: "I Get Around", "Rebel of the Underground", "fukk the World", "R U Still Down", "So Many Tears", "What You Won't Do For Love", "Words Of Wisdom", etc. His remixes after Pac passed were great, too; "Cause I Had 2", "Dopefiends Diner".
*This remix is my favorite version of "Po nikka Blues"