He’s all rotten (slang for a kick-ass rapper) to his core (center), to the bone and all the way down from his hair to his toe.

While he consumes you (as his opponent in battling), the only thing YOU consume is time. So basically, you’re just wasting your time trying to defeat him.

Whether you are a Lil' Wayne fan or not, you may see this as subliminal diss. Lil Wayne has been quoted saying that Eminem didn’t want to rap with him, and he understands because no one can rap with him. What a joke. Anyways, Lil Wayne says that he eats rappers, but Eminem is saying that he eats rappers with the rhyme consuming everyone, whereas Lil Wayne only consumes peoples time.

As long as he’s alive he’ll stay on top of the game, because he is so fly and he is killing shit. He wont rest until he’s dead.

The bible is supposedly an irrefutable reference, so Royce saying he’s big he can squash you and you can take that as Gospel

Petrol swallows is just about the gas the Maserati uses because they are known to have low gas mileage. So trying to get away from the echo that’s so fast he needs a fast car that eats up gas

Royce says he will drop 1000 bodies before he get bodied.
So he will kill a thousand others (bodies) before his own demise.

A Maserati is a really fast sport car (owned by Ferrari) so the echo/impact of his rap spreads fast and large enough to catch a maserati.

First time HE saw a desert eagle he was letting his 44 buss/pop, buss means getting loose (drunk) so he shot with his 44 at the guy aiming a desert eagle on him.

First time YOU saw a desert eagle, you was eating coco puffs while watching Robocop, possibly a Soulja Boy diss?

This explains the difference between a gangster having to deal with real stuff, and normal people discovering this kind of things in a fictional way.

Play on the word “horn”:

• Horn means "motivation" So he needs something to make him up for it, to make him horny.
• Horn could also refer to the weapons of a bull, so he'll only get horny if the opponent is strong enough to stab his clavicle bone.

Your clavicle bone is your collar-bone.

Also:

I need a glass of Patron
Bad as I need a horn stabbing my clavicle bone

He used to have a problem with alcohol and he doesn’t need it anymore—it’s like a gambling addict saying “I need to play some blackjack like I need another hole in my head.” The need is nonexistent.

In a lot of classical poems the main struggle is the character battling their own demons.
The battle my own demons is also a direct reference to the next line, which obviously states he has a problem with alcohol