No one was more surprised than I was to discover that Mr. Rock was my first character who pretty much demands to appear in color. The others don’t mind it, but Mr. Rock doesn’t feel like himself without his turquoise shirt, pink bicorder, and mint green complexion. He’s going to have to get used to it eventually, since I can’t afford to print minicomics in color, but for digital presentation, well, he is going to be in flatted color even if the rest of the drawing is not.
The “three rocks” is a comics trope made famous in Ernie Bushmiller’s “Nancy” and later in the meta meanderings of “Zippy the Pinhead”. In my universe, one of the three (at least) will be a Spirit Rock.
Attentive fans of Mr. Rock will notice that I made a pretty big error in this drawing. How well do you know our favorite Plutonian’s character design, and what mistake did I make?
a cartoonist in Kekionga 
Hmm. Are the stripes on the wrong sleeve of his tunic?
You are correct, sir. I don’t know how I missed it.