OutKast are amazing but Stankonia isn't even their best album. Same can be said for Makaveli.
Doggystyle was great, but Snoops lyrical content leaves me unsatisfied...Dre made that album great.
Makavelli (The Don Killuminati: The 7 Day Theory) is Tupac's best/complete album top to bottom to me. Me Against the World and All Eyez on Me are classics, but it is a matter of opinion which is his greatest. I like Makavelli.
Doggystyle is timeless and has some classic songs (Murder Was the Case, Gin & Juice, Tha ****znit, Ain't No Fun are all bangers). Snoop may not have the tight lyrical content, but his flow and delivery are on point in this, his best album ever.
I guess now that I have thought it over, the greatest rap album of all time has to be Dre's The Chronic. It is truly the definition of a timeless classic that blows outs 99% of the rap stuff that comes out today. It is complete classic album. There are some good emcees out there today, don't get me wrong. I like Lupe, TI, Drake, and Luda.
Here is a list of my all time favorite
albums (ones I always go back to listen too when I am chillin'):
Cypress Hill - Black Sunday
Dre - Tha Chronic
Biggie - Ready to Die
Tribe Called Quest - Low End Theory
Wu Tang Clan - 36 Chambers
Busta Rhymes - When Disaster Strikes
Nas - Illmatic
Jay Z - Black Album & Blue Print
Tupac - All of em
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Black Star - Mos Def & Talib Kweli
Ice Cube - Amerikkka's Most Wanted , Lethal Injection
Fugees - The Score
Bone - E 1999
I have tons of favorite songs from Rakim, Nas, Jay Z, Snoop, KRS-One, Dj Quik, Easy E, Cube, Redman, and many others. Public Enemy and Run DMC are two of my favorite groups along with the Roots, De La Soul, Bone, and Cypress Hill.
I saw the list with the top 50 emcees and here is my top ten:
1. Tupac
2. Rakim
3. KRS-One
4. Nas
5a. Biggie 5b. Jay Z
6. Mos Def & Talib Kweli
7. Krayzie Bone
8. Slick Rick
9. Chuck D
10. Eminem