Many characters do not need to be fully grown to practice villainy. Some are already born villainous or, if not, get possessed, brainwashed, or influenced in their childhoods (e.g. Max). The following villains listed are those who are supposed to be under the age of thirteen or closely resemble children (e.g. Pride and Zhan Tiri).

Teenagers are not to be listed under this category. While teenagers are commonly mistaken for children, these two age groups are actually very different from each other. However, a villain can count for both categories if they age from children to teenagers in their story.

Also, do not include adult or teenage villains who are shown to have been heroic or, at least, neutral during their childhood (e.g. Darth Vader and Eustace Bagge). Other characters who can't apply on this category are those who possess the body of a child for their nefarious plans (e.g. Bill Cipher and Valak). Only villainous children belong in this category.