I'm iller than takin' a hammer and beating your knees
And walking through South Central L.A., bleeding in jeans
(Am I a Blood or a Crip)
If you took a hammer and beat someone’s knee, that would lead them to be crippled, but it would also cause blood. If you can’t decide if you are a Blood or Crip, you’re likely to get shot by both. He makes a similar joke in Marshall Mathers.
Note also that he’s wearing blue jeans (the color of the Crips), that are dripping red blood (color of the Bloods), which makes the line about being confused which one he is go even deeper.
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