Malefactors are troublemakers who engage in loutish behavior and acts of vandalism, they tend to be younger villains but can be of any age and share some similiarities to bullies - however malefactors aren't necessarily targetting individuals as bullies do but rather engage in antisocial behavior either for fun or as a form of rebellion.

Examples of Malefactors: Vandals, Thugs, Gang Members (especially Street Gangs) and villains that generally have a bad attitude and lack of respect for other people or society's norm.

Green Goblin

Discord (My Little Pony: Friendship is Magic)

Beavis & Butt-head

RoboGadget

Stripe/Mohawk

Triple H

The Rowdyruff Boys

Gangreen Gang