Steve Vai got his seven-string prototype just in time for Whitesnake’s Slip Of The Tongue, using it on every song, as well as on Passion And Warfare. Hear it clearly on Judgement Day, The Audience Is Listening, and I Would Love To. Steve made his powerchords crunch harder by barring the low B string, creating a crushing second inversion. Thanks to Vai's influence, the Ibanez Universe became the first mass produced seven-string. Then Korn got a pair, changing metal permanently.