And I'm a million leagues above you,
A league is an old unit of length that’s rarely used today. Em is saying that his self motivation has helped him be crazy better (ranked higher) than all his competition
Em’s not just out of everyone’s league, as in being a “major-league” player going against “minor-league” players, he’s a million leagues better than other rappers!
Leagues as in the unit of length: Em is literally way above other rappers, which also fits in with the imagery of God. He’s a million leagues above mere mortals, in the heavens.
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