The line "It's the rap god, back with a new track" is a stylized and self-assured way to start a rap, reflecting the braggadocio often found in hip-hop culture. It's not necessarily something I would always use, but it's emblematic of the confidence and assertive persona many rappers adopt when performing. The phrase "rap god" could be a nod to songs by well-known artists that have used similar terms to assert their dominance in the rap game. Each rap or artist might have a unique way of introducing their work, and this is just one example.