This topic is so frustrating because no one including @canary1 the OP has defined what makes “greatest rapper” in terms of criteria.
This thread has instead become “here’s my favourite rapper” with a brief argument, or no argument.
Here’s four categories which explains why the same names keep coming up
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• People think greatest rapper means “most socially conscious”. These* *folk don’t include record sales, fame, or longevity in their judgement. They believe all rappers should be held to a higher standard than pop artists. Anyone who speaks about harsh realities without giving social commentary is immediately discounted. People in this category have stated Nas, Akala, Lowkey, Mos Def, Talib Kweli (seriously?!) etc.
•. People think greatest rapper means their favourite rapper who is internationally famous and has had a memorable discography this category doesn’t take into account technique or subject matter. It’s all about “the biggest name” based on sales, nostalgia, recognition. So 2Pac, Biggie, LL Ccol J (yeah he was the biggest, perhaps the first solo star, once!) etc.
• People believe greatest rapper means the best mic technique and rhyming ability This is where Eminem reigns supreme and why he’s in here. See also Jay-Z, and any other technically gifted MC.
• People can’t understand why groups aren’t included and so name their favourite group We have already seen Wu Tang, A Tribe Called Quest etc named in the thread, and all had great MCs and some solo stars. But are their solo stars “the greatest?” Rae and Ghost I’d argue should be up there for sheer influence. But the greatest?
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for me the greatest rapper to do it was Lil Wayne.
Technically runs rings around most rappers here
The rap scene of the last 15 years has been built around his entire cadence, image and persona. I could write a list of a dozen hitmakers today whose rap name starts with “Lil”. They are all musical sons of Wayne.
Legendary discography - Tha Carter III is the equivalent of Never Mind the Buzzcocks in terms of how it shaped and changed rap.