If a UFO had came for me, I'mma come back with the head of an alien
UFO’s are claimed to abduct humans for research. Kendrick is dope enough that the aliens would realize the potential within Lamar’s brain, so they would keep his head for further research, and give him an alien head.
It’s also possible Kendrick means he will literraly come back with a chopped off head of an alien. So if a UFO came for him, they would wish they never did.
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