Delusional-type villians are characterized by or holding idiosyncratic beliefs or impressions that are contradicted by reality or rational argument, typically as a symptom or mental disorder; in other words, they commonly make false assumptions. These can be if they believe themselves or someone else as a different species, a god, a real being, a good person, a genius, a handsome or beautiful person both visibly and within. Even those who know they are evil can be deluded.

The types of deluded villians who actually believe themselves to be good people think that what they do is right; this makes them similar to Vigilantes and Anti-villains, but unlike them, a delusional villain's cause is sometimes nothing close to noble. No matter how horrible an act a delusional villain does, they will always see it as a noble act; thus, even though they see themselves as good, many delusional villains can be Pure Evil (e.g. Akainu, Makuta Teridax, Judge Claude Frollo, Koba and Zant). 

These types of delusional villains also believe that whoever disagrees with or opposes them is a bad person. Therefore, they are very paranoid and pay little to no attention to the others' opinion. These villains may be greedy or hypocritical, but cannot even see it. Worse, some of them tend to blame someone else for the destruction they cause (especially those who oppose them) while, in reality, it was their fault.

The scope of these villains' delusion can range from being a relatively minor trait (usually just simply believing they are doing good and not fanatical about it) to dangerously extreme to the point of mental illness (such as villains who are extremely outspoken that what they are doing is right and there is absolutely no chance to convince them otherwise).