Once they caught us off-guard, the Mac-10 was in the grass and
I ran like a cheetah with thoughts of an assassin
This section starts a more focused narrative; Nas is known for these “stream of consciousness” bits: he is ambushed by his enemies and runs towards his Mac which is on the grass (the Mac 10 is a fairly large semi automatic weapon. Pavements are not the best place to hide one)
The question of who Nas is shooting at is tough to sort out — who does the “they” in “they caught us off-guard” refer to? One possible antecedent is the Task Force, implying that Nas is shooting at cops. On the other hand, in the next line Nas is shooting at “niggas”, not a typical way to describe New York’s predominantly-white police force. So he is refering to a battling a rival crew. He’s actually remembering an incident involving the same dudes who once caught them off guard and tellin what happened during that instance
Note the metaphors of jungle predation: grass and cheetah.
A similie, the cheetah can run faster than any other land animal— as fast as 112 to 120 km/h in short bursts covering distances up to 500 m (1,600 ft), and has the ability to accelerate from 0 to 100 km/h (62 mph) in three seconds—– Nas you’re pretty damn fast!
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