Rock a V and an effective God is invincible
“V” means victory here, as the GZA had likely just defeated his opponents lyrically on the mic — since this is mostly about MC'ing with an extended chess metaphor, he has captured some pieces or Checkmated the King.
“V” could also mean “V-neck”, as in wearing (rocking) a V-neck shirt. Dressing a certain way can make you feel empowered and will make others take notice. The way GZA dresses up the mic is with his lyrics, often using extended metaphors and sick wordplay.
Here’s a pic of a girl rocking a GZA V-Neck T-Shirt:
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