Aggressive lyrics and dirty sound beats characterize this kind of Rap. But the one that stands out in particular is that Hardcore rappers follow a discipline dictated by themselves and keep us representing it best.
The dissing is very common, where a rapper devastates another rapper with extremely sharp rhymes to show which is the superior technique. Lyrical themes include violence, prostitution, selling drugs, criminal activity, religion (in blasphemy term), and government conspiricies.
They see violence not as a crime but as a simple confrontation, who loses die who wins survive.
Hardcore is a lifestyle.