The Teenage Mutant Ninja Turtles were always meant to be a bit tongue-in-cheek, and even the far more serious comic book version often approached ideas of mutation, vigilantism and teenhood in a playful manner.
Villains like Krang, Bebop and Rocksteady and Leatherhead were already pushing the boundaries of what constitutes a challenging villain, but they're pushovers compared to the crazy creations that made io9's list of Thirteen Of The Most Ridiculous TMNT Villains Of All Time.
It's almost like the folks who came up with these whacked out baddies were just drawing names out of a hat, taking the whole idea of mutation to a most ridiculous extreme.
A hybrid monster with the power of five classic monsters in one? I guess even movie monsters aren't immune to The Ooze. A sattelite-human hybrid named Vid Vicious? Never mind the bollocks, just aim for his tin can head!