'''Basic Trope''': A bad guy turns into a good guy.
* '''Straight''': [[MadScientist Dr. Evilstein]] turns against [[EvilOverlord Emperor Evulz]] and starts helping the heroes when he's betrayed by his master one too many times.
* '''Exaggerated''':
** Bob seemingly crossed the MoralEventHorizon back in his youth and kept doing increasingly evil deeds on a daily basis. Then, he suddenly sees the light and turns into [[BigGood a force of good so big]] that he rivals TheHero himself in goodness. Eventually he becomes [[IncorruptiblePurePureness a paragon of virtue]].
** HeelFaceTown
** All of the Villains are redeemed by the end of the story.
* '''Downplayed''':
** Alice tames a wild cat that's been going about her house.
** TookALevelInKindness
** ReformedButNotTamed
** HazyFeelTurn
** Going from a JerkWithAHeartOfJerk to a JerkWithAHeartOfGold
** The bad guy was a PunchClockVillain.
** DefrostingIceQueen
** A character is an UnwittingPawn being manipulated by the villain but immediately switches sides once they know the truth.
* '''Justified''':
** [[BeingEvilSucks He got sick of being evil]] [[MyGodWhatHaveIDone and became filled with shame and remorse]], [[TheAtoner and wants to repent for his sins]].
** He was a KnightTemplar or WellIntentionedExtremist who had a HeelRealization that he's gone way too far, [[HeWhoFightsMonsters and became exactly what he hated]].
** He was [[EvenEvilHasStandards disgusted with how evil the main villain was]], and decided he had to cut ties with him.
** His goals are much more readily fulfilled if he works for the heroes than the villains.
** Evulz has treated him like shit for years, and he is taking the opportunity to [[TheDogBitesBack pay him back with interest]].
** He ''always'' wanted to do the right thing. The villains simply tricked him into [[MyMasterRightorWrong believing]] their cause was just and heroic. Upon learning that he was working for the bad guys all this time, he abandons the group to join the ''real'' heroes.
** ReformedCriminal
** Doctor Evilstein would have put up with the abuse... until Emperor Evulz threatened his kids. Evilstein [[PapaWolf betrays Emperor Evulz for his children]]. When the heroes attack, Evilstein makes sure Evulz plan fails at the ''worst'' possible time... [[ActionDad or Evilstein himself gets off the bench]] and [[EvilVsEvil attacks Evulz himself]].
* '''Inverted''': FaceHeelTurn.
* '''Subverted''':
** He's [[FakeDefector only pretending to turn on the bad guys]].
** HeelFaceDoorSlam
** FalselyReformedVillain
* '''Double Subverted''': He's [[FakeDefector only pretending to turn on the bad guys]]... at first, but then he starts BecomingTheMask.
* '''Parodied''':
** The hero gives a speech about ThePowerOfFriendship so SickeninglySweet most viewers are in a diabetic coma... and the villain gets [[WingdingEyes heart shaped eyes]], stops his EvilPlan and opens an OrphanageOfLove.
** He sees the errors in his ways in being team Coke; he's now team Pepsi.
* '''Zig Zagged''': HeelFaceRevolvingDoor.
* '''Averted''':
** It's clear right from the beginning that he's still evil... but his goals align with the heroes for now.
** Evilstein is a CompleteMonster, and thus will never join the good guys' cause.
** RetiredMonster
* '''Enforced''':
** "This bad guy is really popular; we need to make him into a hero so we don't get into trouble with the MoralGuardians."
** The author of the work is a Christian and he wants his work to preach about forgiveness.
* '''Lampshaded''': "I was upstaged by an EldritchAbomination that [[PlanetEater wants to eat our planet]], changing sides may be cliche, but it's also ''sane."''
* '''Invoked''':
** TheAtoner
** "You never know, he might stop his plot if we can convince him using the ArtifactOfDeath will kill all life on Earth."
** The hero gives Dr. Evilstein a [[KirkSummation compelling speech about how]] BeingEvilSucks.
* '''Exploited''': Suspecting that one of his minions will eventually join the good side, Emperor Evulz secretly implants [[WhyAmITicking a bomb within him]]. Not only it will get rid of him, but with perfect timing it might even kill all the heroes in the process.
* '''Defied''':
** "You think I'll stop just because it would save the life of my beloved? ''[[EvilLaugh Hahahaha!]]'' [[LackOfEmpathy That's funny]]!"
** RedemptionRejection
* '''Discussed''': "You know, it always seems these NobleDemon types find RedemptionInTheRain".
* '''Conversed''': "Well, whaddya know, the most sympathetic of the bad guys was redeemed."
* '''Deconstructed''':
** HeelFaceDoorslam, when it results in death.
** The bad guy switches sides and helps save the day... but rather than find redemption, friendship, love or even gratitude, he promptly goes to jail for all the crimes he's done. By the time he's released he's not hailed as a hero, but forgotten. Those who ''do'' know who he is treat him [[ReformedButRejected as a reject]]. Why did he switch sides again?
** The villain tries to atone for his past misdeeds, but quickly learns that redemption is not a clean, instant process and frequently [[TragicVillain resumes his old crimes]].
* '''Reconstructed''':
** The bad guy weighs the possibilities, realizes that changing sides is profoundly stupid... but still feels EvenEvilHasStandards. So he'll help stop ''[[EnemyMine this]]'' bad guy, and go to jail.
** The repeated failures to stay good motivate the villain to work harder to push himself away from evil. Through increased effort and patience, he manages to become a genuinely good person.
----
Back to HeelFaceTurn.
----
%% Optional items, added after Conversed, at your discretion:
%%
%%* '''Implied''': ???
%%* '''Plotted A Good Waste''': ???
%%* '''Played For Laughs''': ???
%%* '''Played For Drama''': ???