Born with a heart of gold, now mostly cold and scarred
En guard, choose your weapon, or get to steppin

from Gang Starr (Ft. Big Shug & Freddie Foxxx/Bumpy Knuckles) – The Militia Lyrics 4 on Rap Genius

He means that he was born with a heart that was capable of caring and love, but the life he has lead has left his heart tattered and “scarred” and/or he has suffered severely enough from heartache but has recovered from it every time.

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