I buy a bunch of 'em and put it on my black card
Now I got some street cred, use it 'til it's maxed out
This black card line is also referencing the n-word line above it. He’s saying he should buy a bunch of ‘n-words,’ use them to gain street cred, and keep buying them/street cred until the Black card’s maxed out.
Not to be confused with the other black card…
Also It’s a double meaning that he will “buy” and then “put it on my black card”, meaning a credit card linking to a bank account with a lot of money. He will use his street cred until his card is maxed out. For those of you who don’t know, it takes a lot to max out a black card.
Another part of the double meaning is the line above references “N-word” and then he says “black card”, i.e. pulling the race card.
“Cred” is of course short for “credit,” continuing with the credit card metaphor.
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