In the jungle with the leaders, we them lions, you the cheetahs

from Black Star – Definition Lyrics on Rap Genius

Meaning

In the jungle (i.e. the concrete jungle of Brooklyn or the treacherous landscape of rap music in general), Mos and Talib stand amongst the leaders as metaphorical lions (aka the “King of the Jungle”). They ain’t Simba, they grown-ass men!
The last word is a double entendre of the homonym cheetah/cheater. Their opponents are cheaters because they take the easy route to fame and don’t focus on lyricism. The cheetah, being the fastest land animal, has the speed to flee from the superiority of the lions (Mos and Talib). But as this video shows, it has no chance of competing with them:
http://youtu.be/3IwDHvNxjJo?t=17s

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