Many heroes walk a thin line between good and evil; indeed, many heroes have fallen into despair, rage or even madness and once-proud heroes descend further into the path of evil, often fighting against people they once protected or fought alongside.

Originally protagonists or forces of good, these villains turn evil due to events in their lives such as being corrupted by other Villain, desiring revenge, failed love relationships, betrayal or any unresolved traumatic experiences in which they question whether or not the good side is worth fighting for.

A Fallen Hero - or hero turned to the dark side - is usually the end result of a protagonist exposed to a Corrupting Influence, Deal Makers, Brainwasher, and occasionally an Extortionist, Blackmailers, or even Bond Destroyers. However, some heroes may turn for more greedy reasons (i.e. "From Sugar to Excrement" scenario).

In the worst cases, some heroes turned to the dark side can become Purely Evil to add drama as they are willing to be evil without any remorse or positive qualities after all. Good examples include Makuta Teridax, Herrscher of the Void, Terumi Yuuki, Dark Danny, Isaac Ray Peram Westcott, Zamasu, Griffith, Grand Moff Tarkin, Zombie Giant-Man, Scar and Shinnok. However, some of them can still redeem themselves, especially if they were former henchmen who eventually betrayed their masters when they come to realize just how evil they really are, such as Big Baby and Speckles.

There are various scenarios for why these individuals turned to the dark side, though the said individual often to fell onto multiple scenarios altogether:

• From Zero to Nightmare: A scenario where the said hero turned to the dark side in this way often became a shocking event for either viewer, heroes, or other people that found out about this. Reason of this mainly because the said hero always looked down upon, his/her existence was ignored, and/or worse, considered as an outcast or an individual that often being abused by other people that dislike/hate them (either the Big Bad or merely minor villains in the story) no matter what kind of good/heroic efforts that he/she did for others' acknowledgement. Once this individual turned to the dark side, they (usually) became feared by many people, includes heroes that faced them. Good examples of this include Savitar, Dave, and various incarnations of Frankenstein's Monster.
  • From Victim to Villain: In this sub-scenario, these characters were once people who tried to be friendly and do good, but were rewarded with injustice and ingratitude by society. Often, they were victims of bullying or abuse, and eventually they were pushed so hard they finally snapped and now seek revenge on the very society or people that shunned and hated them. Despite their tragic nature, very few of these characters actually are redeemable. Not because they are Pure Evil, but because they almost never forgive or forget, and/or are now completely insane and cannot be reasoned with. Often, they enact the exact same cruelty, or even worse cruelty, on their tormentors, and even innocent people, making them no different or even worse than their tormentors. Examples include Lucy and Andrew Detmer both of whom, after being bullied and abused by others, finally went killing sprees, became even worse than their tormentors, and in the end, had to be killed in order to save others.
• Not good with Rejection: A character may have once had an acquaintance or love interest who befriended them prior to their turn to the dark side. One day, the individual either made an offer, confessed their love, or presented a certain proposal to the hero(es) which the hero(es) rejected. The individual, unable to cope with this, thus decided turned to the dark side. Generally, the worse the hero(es) reject(s) the individual, the farther that individual turns to the dark side. Good examples of this include Bill from Kill Bill and Alex Forrest.
• Being an Extremist: A character has well-intentioned goals for the greater good, but their methods and ultimate ends are proven to be very extreme to the point that they become something that is greatly despised, whether by those whom they know, the heroes, or themselves. The said actions may even potentially drive them to the dark side as well, even if most of these characters become Anti-Villains in the process. Good examples of this include Nathaniel Barnes, Renegade Shepard and Damon Gant.
• From Sugar to Excrement: These characters were once highly revered and loved by their peers but turned evil, either by greed, lust or simply because they were "tired" of being good, bringing shock and despair to those who knew them. Examples include Baron Kelvin, Tankor and Yoshihito Kanamori.
  • From Defender of life to Power-Hungry: In this sub-scenario, these heroes originally wanted to protect the lives of their people but eventually come to realize that they can use their powers to destroy anything to get more power than before. Examples may include Zanza, Sunset Shimmer and Ultraman Belial. Another example is Elgen Inc., formerly a medical equipment manufacturer that accidentally created electric rats using one of their medical devices and gained control of the world's energy.
• Being Possessed/Brainwashed: Once heroic, these characters were either possessed or brainwashed by another villain or corruptive presence, and consequently became villains. However, this is the rarest and most controversial form of a hero turning to the dark side since they did not turn evil by their own free will and essentially had to be programmed into being villainous. Examples may include most of the characters from the Possessed/Brainwashed category, such as Liu Kang from Mortal Kombat X. Most of these characters redeem themselves after snapping out of their current state. Another example was Angor Rot from Trollhunters, who was a hero to troll kind and tried to help people who are unsafe in Gunmar’s war, only to be brainwashed by Gunmar’s indirect creator, Morgana into being evil when he asked her power to protect his village. By the series finale, Angor redeems himself after he realizes whom he was and how eveil and cruel he once was.
• Desperation: These characters were people who, despite having followed the rules of life and following their principles, are even affected by the crisis both socially and economically, and puts them in danger of putting their daily lives or the things they have managed to maintain during years ( a company, for example) to ruin; this causes these characters to fall into (irrational) despair, in order to prolong, or even to "eradicate" the inevitable, forcing them to break the rules and act immorally, whether stealing things (such as money obviously), kidnapping, or even killing the people who persecute them, either for economic reasons, or because they witness their crimes. A good example includes Waternoose III Henry Waternoose III, he was only driven to villainy out of desperation to keep Monsters, Inc. afloat in the midst of the energy crisis, as well as due to stressful financial problems and his responsibilities as CEO. Mr. Waternoose became more villainous and manipulative, as this drive and desperation stripped away his morals and was determined to not let anything stop what he believed would be the best way for the company to keep going, never bothering to look for alternative energy sources.

Notes

Please note that a character has to have been established as a hero before turning evil.

• Pure Good heroes can't turn evil and become fallen heroes because they're completely immune to corruption. If some heroes were considered to be Pure Good but eventually turn evil, it means that they were never Purely Good in the first place.
• Morally neutral characters (a la "average joes") or characters initially un-involved with any side of the conflict do not count (e. g. Lots-O' Huggin' Bear, Balthazar Bratt, or Jerry Rassic ).
• False heroes, if they never were good, do not count either (e.g. Kristoph Gavin, Napoleon of Animal Farm,, Prince Hans from Frozen) and (Disney)|Scar]] from ‘’The Lion King,’’

Note that Tragic villains do NOT automatically mean that they are heroes turned to the dark side. This category is meant for villains who used to actively work for the good side. Also, this kind of hero is the polar opposite of Pure Good heroes that are absolutely incorruptible.

• Also, do not create pages based on this category, as long time heroes who were only briefly fallen or on and off "jerks" (Such as Barnacle Boy who only fell to the dark side over a Silly Meal and called himself Barnacle Man in the Spongebob Squarepants episode Mermaid Man and Barnacle Boy V but then eventually redeemed himself, Luan Loud who only turns evil in the April Fools episode and does eventually learn her lesson in the end or Mushu who only was bad when he deliberately tried to put end Mulan and Shang's love to save his career in Mulan 2 but then eventually redeemed himself at the climax of the film) do not count.

See Also

• Fallen Heroes on the The Evil Wiki.
  • From Nobody to Nightmare on the The Evil Wiki.
  • From Champion to Power Hungry on the The Evil Wiki.