Villains who can actually serve very important purposes and need to be kept alive despite their evil deeds. No matter how sadistic, bloodthirsty, cruel, or even how much they are hated, these villains have to live or something terrible will happen. However, once they fulfilled their purposes or if there is a good / less evil alternative and they still choose not to redeem themselves, whether they get killed off or suffer a demise no longer matters, as they are no longer needed at that point and still have technically done evil things.

These characters are similar to Virtually Resourceful characters, but are obviously opposed to their alignment. Also, these characters are usually created to keep the story relatively three-dimensional.

See the trope page this category is based on

Notes about Complete Monsters[]

Complete Monsters ,Near Pure Evils and Inconsistently Heinous villains CAN be necessary, regardless of how wicked they are. Despite being very evil in the setting that appear in, their status, power, or occupation may be necessary to uphold the order of the place that the story takes place in, thus they are in a way "Necessary Evil". Technically, this include Purely Evil villains who fall under the fourth, fifth (in circumstances like these, it is considered Evil Vs. Evil), third, sixth, seventh, twelfth, twentieth or twenty-first criteria - and ONLY these criterias.

This is not a redeeming quality as the villain is still dangerous to the setting that they happen to be necessary in. For example, abusing or enslaving those around them while upholding stability to something greater that they are apart of. Nevertheless, keep in mind that adding a Pure Evil under Necessary Evil MUST remain exceptional.

In another extreme case, there are Complete Monster/Near Pure Evil villains that can still be necessary to the story itself from where they came from. This happens only when the villain is the "key" character to the work from where they came from. In other words, "without the villain, there is no plot".

Villains who qualify[]

Villains who fall under at least one criteria are Necessary Evil:

1. Some anti-villains with the intent to help the hero or to save a large number of people. Often, these characters are considered anti-heroes.
2. Villains who are keeping a much worse evil at bay (e.g Professor Brezhnev, Toad).
3. Jerk employees and employers that actually are capable of doing their jobs and it's made very clear the business cannot succeed without them.
4. Villains preventing catastrophes, including the end of the world or universe, with their mere presence or actions (e.g. Mario’s status as the Avatar means that if be dies, the universe will be destroyed).
5. Evil vs. Evil scenarios where one of the villains is the only subject strong/powerful enough to defeat the more dangerous threat (e.g. SMG3 and Wario were the only people able to get Waluigi therapy to help him redeem, SpongeBob SquarePants was the only person able to defeat The Tortured One).
6. Unlawful businessmen that can provide a product or service that is needed or well-liked by people. This can also apply to entertainers who perform or create to please and entertain people.
7. Villains performing villainous acts that lead to beneficial results/consequences, whether the result itself was what they intended or otherwise. Some cases of this instance show where villains whom their actions was turned out only to merely trained/molded the heroes so the said heroes can become a better savior (in which they often revealed in the end). Other cases, however, show that either their actions are the key for their future downfall at hands of heroes that they antagonize or made hero realized the grave situation that everyone faced (e.g. Francis murdering Desti caused Meggy to win Splatfest and receive a ticket to Port Aurora from her friends which resulted in her saving Port Aurora from the far more dangerous Sir Benedict Cumbersnatch, Niles knocking SMG3's guardian pod off course would indirectly cause him to help SMG4's Gang with defeating Waluigi).
8. Wealthy villains that helped the city they live in.
9. Amoral entities that must keep the balance of nature in check.
10. Family breadwinners.
11. Villains with important informations that are necessary for the heroes and the other characters to either save people or defeat more dangerous evil-doers.
12. Some heroes who turned to the dark side that had everything related to their evil actions upon their fall from grace exposed, would led to undesirable consequences.
13. Villains from the Lawful Neutral alignment who keep order, and it's obvious that situation would be worse had they not been present.
14. Hostile biological species, tribes, or civilizations that, while hostile or xenophobic, are capable of producing children and families. Killing of a naturally hostile race, civilization or tribe would still be considered an act of genocide.
15. Evil teachers who keep unruly students in line.
16. Alter-Egos or powerful entities within a hero, the ones that has possessed the hero, or grant them their powers, resulting in them saving his/her lives from time to time.
17. Former villains that joined, or at the very least, helped the heroes.
18. Villains who saved a protagonist(s), attempt to sacrifice themselves to save a protagonist(s), or sacrificed their lives to save the protagonist(s).
19. Double agents that are on the side of good and pretend to be evil. These people can be either friends of the heroes whom originally at odds with heroes but ultimately chooses to switch side with the heroes and leaked the antagonists' evil scheme on them.
20. Dark Forms, Devils, Gods of Evil or other personifications of evil that are literally the source of evil. If they are destroyed, evil would cease to exist, and life would no longer be able to feel sadness, anger, or any other negative or evil emotion and be forced to feel positive all the time, be incapable of doing anything evil or negative, and think that negativity is unnatural. So villains who are the source of evil have to be kept despite their evil influence (e.g. Nekrozoth).
21. In video games, certain evil creatures such as the hostile mobs from Minecraft, that can be farmed for useful items (killing a Wither will give you a Nether star, which is the key ingrediant to make a beacon, killing an Evoker will give you a Totem Of Undying, which prevents you from dying, Blazes can be farmed for their rods to power your brewing stand(s), the Ender Dragon can be re-spawned to collect Ender Acid to make lingering potions, and so on).