Best ever? Damn, that's a tough one.
A few that I keep getting back to are...
Gift Of Gab
Tech n9ne
Sage Francis
MC Supernatural
KRS-One (even though I've heard far too little of his work)
Best group, I think I would still have to say Bone-Thugs. Not lyrically but definitely technically. Even though their quality is inconsistent, they had crazy tight flow on their good days.
i know everyone thinks it's cool to say Pac is the GoaT, but come on guys..
No doubt he has some dope songs, but he says the same shit throughout his career - and by that i mean he spits the same lyrics over and over - just over different instrumentals (i know thats not his fault).
he is in the top 10 influential rappers of all time, but not in my top 10 mc's ever.
In no particular order.
Guru
Krs
Mos
Talib
Wallace
Meth
Mathers
Common
J-Live
Cyne
Jay-Z did a remake of "Me And My Girlfriend" originally done by Pac, but with one big problem. He had no idea that Tupac has the deepest lyrics and that the song was actually about the collection of pistols he had owned in his life, and not about an actual girl. Jay-Z, Lil Wayne, and Nelly get the worst rapper awards. Jay-Z only for the huge Me and my Girlfriend screw-up, but still he deserves it. Deepest lyrics that sometimes contain double and even triple meanings goes to Tupac. Nas is arguably just as good as a lyricist though, he just has smaller balls.
"Bullets to my nuts only made my balls fatter." Tupac
here's a good song, artist Vordul Mega (part of Vast Aire's group)
http://www.youtube.com/watch?v=TyHCKznEkDo
"Megagraffiti"