In "Smurf on the Run, after Hefty felt that Sassette is being "think-headed" over the belief that Gargamel will one day become good Nat agrees with him by saying, "Yeah! Every Smurf knows that he is the nastiest, most evil human on the face of the earth." However, the voice that came out of Nat's mouth is not from him, but from Slouchy's. See more
How can such a smart Smurfling be so think-headed when it comes to Gargamel?
Natural 'Nat' Smurf
[Slouchy's voice is heard from Nat's mouth
Yeah! Every Smurf knows that he is the nastiest, most evil human on the face of the earth.
Oh my! Look at me! I'm blushing!
But I just know that I can change Pappy Gargamel if I had the chance. After all, he must have some good inside of him. He helped to create me, did he?
Well we all make mistakes!
[Jumps in front of the Smurfs