"With respect to all of the artists, the song doesn't really do it for me, it feels a little artificial," Ice said of the song in a recent interview with GQ. "What I mean by that is that it sounds like a bunch of executives in the corporate world put it together. It really does not fit the theme of the Ninja Turtles legend. I think you have to understand, and be a true Ninja, to possess the Magic to really pull off the secret sound."
The "Ninja Turtles legend" Vanilla Ice is talking about just happens to include himself. Back in 1991, Ice performed "Ninja Rap" for the Teenage Mutant Ninja Turtles II: The Secret of the Ooze soundtrack, and also appeared in the film itself during a pivotal scene.
The new Teenage Mutant Ninja Turtles, directed by Michael Bay, hits theaters on August 8.
UPDATE: Wiz Khalifa has responded to Vanilla Ice's comments, saying that he doesn't have beef with the rapper and that he respects his opinion on "Shell Shocked." Check out his response at the 5:11 mark of this video.