The Adversary

''Like the Villain but smaller. Not physically, of course.''

The non-adventurous Villain whose intentions might not necessarily be evil but are still negative and usually harm others in some way. They likely have some distaste for or rivalry with at least one of the members of the Main Cast (if not the entire Cast) and constantly tries to triumph over them, only to be thwarted at the end of the plot. The Adversary has virtually no chances of converting to a Good Guy, unlike the Villain. The Adversary could also do something that harms the Main Cast although they didn't intend any harm and might even feel bad about their actions.

In children's media (especially educational), the Adversary may repetitively try to get in the way of the Good Guys by causing lighthearted mischief at best and realistically nearly fatal happenings at worst. They never get as close to success as a true Villain, their adventurous counterpart, might. The Adversary in this sense might not even be aware of their negative doings at times and will then work or at least comply with the Good Guys on fixing things and getting them back to normal. This makes many Adversaries unable to be considered truly evil. Children's media Adversaries appear more often than Villains do by being in (just about) every episode of TV shows.

The Adversary shouldn't be confused with the Rival, who can be considered a "friendly Adversary" to the Main Cast. Where the Rival only competes against somebody from the Main Cast and doesn't mean to hurt them, the Adversary truly wants to hinder the Main Cast and tries everything in their power to get their way. It could be that somebody from the Main Cast Broke The Vase with the Adversary or that the Adversary is just a general villainous character who doesn't target anybody in particular unless it's for some kind of temporary plan of theirs.