What are some really good gangsta rap albums/artists?

I am trying to find more gangsta rap albums/artists that are similar to Three Six Mafia's Chapter 2: World Domination, Lord Infamous Blood Money and Bone Thugs N Harmony E. 1999. Pretty hard and violent. It's hard to beat those albums/artists as those are basically the best out there. I've tried N.W.A., but that one didn't do it for me.