Sylvester is typically portrayed as a short, blonde man with wide, pleasant face. He usually is seen in his janitor's uniform of white overalls and painter's cap, often with a yellow "non-smiley-face" button on it. He is often depicted as mute and gentle of nature.
It would seem that Sylvester appeared in every single Cracked publication, even if only in the form of reproduced stock art, so a list of his appearances is pointless. If it's Cracked, he's there.
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