Wayne often refers to himself as a Martian and/or a goblin; since he is obviously not human, he’s trying to find a species where he belongs (he says the same thing in his E.T.-based song “Phone Home”)
Space Jam was a movie that features, among others, Marvin the Martian
He’s saying there is no way you can even remotely compare yourself to him because he is not human. in other words, his flow is so amazing that it isn’t humanly possible to reach that level of awsomeness unless you are immortal, and since he is not a human being, he is the most amazing rapper
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