Warning: While not always a Death Trope, can often involve that, so be wary of spoilers.
Heel-Face Door-Slams in Comic Books.
- Blackest Night: After battling Black Lanterns attacking them, Slade apologizes to his children for all he did and offers to make amends by starting anew. Furiously, Rose calls him out on how much he messed them up and storms off declaring she doesn't want him in her life.
- Sometimes used in Chick Tracts, where a character is considering accepting Christ but dies before being able to act on it and ending up in Hell. The idea is that one can not put off accepting Christ as death may happen at any point but in typical Chick fashion, it comes off somewhat Anvilicious or even paints God as a bit of a Jerkass.
- In Crossed, Geoff confesses to having been a Serial Killer before The End of the World as We Know It and had been working to atone for his crimes by helping others. Unsurprisingly, the rest of his group isn't thrilled to learn this and the next morning, Kitrick takes him for a walk in the woods and comes back alone.
- Deadpool tries really, really hard to be good. He does. Really. But it's just so much easier to kill people and he has no attention span and people are SO annoying and... That's not to say he's a Heel, but rather that despite all his attempts to be good, and all his actually good acts, he's still a Psycho for Hire. It doesn't help that whenever he does something so good that he'd likely be recognized by the world for his heroics, there's typically either no one (reliable) around to witness it or some outside circumstance screws it up immediately afterward. This culminates in Secret Empire when Deadpool sides with HYDRA because Captain America is there, slowly realizes he's made a mistake and makes the mistake of trying to help Maria Hill, who ends up dropping a parking deck on him. He escapes three days later, three days too late to make any difference as the heroes had saved the day by then.
- In Fantastic Four (2018), Doctor Doom makes an attempt at Love Redeems and tries to bury the hatchet with the Four, even inviting them to his wedding. Then it's revealed Johnny slept with his fiancée, with Namor laughing his ass off in response, and everything immediately goes to hell.
- Legion of Super-Heroes: V4 has a wretchedly sadistic example in Sun Boy, a long-standing Legionnaire who'd been seduced into being the public face of the evil Earthgov. Faced with an impending disaster, he tried to put his costume back on and save the city, only to a) meet with public scorn and b) be caught in the explosion of a fusion reactor. Wait, we're not done: due to his powers, the explosion didn't kill him (actually, due to his powers the explosion shouldn't even have touched him; oh well); instead it left him a mangled, screaming, burning wreck. He then spent the next year and a half on life-support, in agonizing pain and reliving his worst memories, until finally he was shot by his lover/handler (who then killed herself). That door slammed so hard it broke.
- In The Mastermen #1, Overman attempts to right the wrongs of his making Nazi Germany become the new world by lying about Human Bomb's physiological differences from most people. Unfortunately, Jürgen Olsen figures out that he's not in favor of Hitler's vision and has sympathies with the Freedom Fighters, and thus betrays him, leading to Overman's downfall.
- In Nikolai Dante, during the Battle of St. Petersburg, a random mook suddenly had a change of heart and shoved a machine gun operator out of the way to stop him firing on the Romanov forces. Immediately afterwards, Jena, unaware of what he had just done, stabbed him in the chest.
- The Powerpuff Girls refuse to believe that Mojo Jojo has gone straight and opened his own restaurant ("Monkey Business," issue #67), in spite of the fact that everyone loves his cuisine. Twice, the girls cause an alarm that sends everyone for the exits and subsequently publicly apologizing for it. The third time, though, is enough for Mojo. He quits his restaurant and goes back to being a villain.
- Red Skull once had the chance to at least die repentant. After being locked in a shelter in the middle of nowhere for days, starving and alone in the dark, he finally resigned himself to his fate and for the first and only time in his life, felt remorse for his evil deeds and privately conceded that he deserved this fate. But even this would be denied him, as was rescued shortly after, regained his will to live after seeing Captain America and remembering how much he hated him... well, he forgot everything he had considered down there, and after telling Cap as much, began ranting about how he would get revenge on Magneto.
- Spider-Man:
- Mac Gargan, a.k.a. the Scorpion, ends up wandering the sewers at one point, depressed but with a clearer head than he had had for a long time. Eventually, his sanity starts to return, and he is about to make a Heel–Face Turn when Spider-Man having depression issues of his own, finds Gargan and attacks him savagely ignoring Gargan's pleas that he had changed. Gargan then goes crazy again to save himself and continues his life of supervillain debauchery, first as Scorpion, and later as a new Venom.
- Another example was Shriek, one member of Carnage's group of killers during the Maximum Carnage fiasco. Some months after that fiasco, she broke out of Ravencroft Asylum and kidnapped Malcolm McBride (formerly Carrion, who was human at the moment, the virus inside him in remission) and stress caused by the ordeal caused him to become Carrion again. After seeing Carrion show some sympathy for his mother, Shriek had a brief moment of sanity and actually tried to absorb the Carrion Virus into herself, trying to make a Heroic Sacrifice to save Malcolm. She did save Malcolm, but the virus didn't kill her... And for poor Shriek, this heroic act only made it worse for her. It drove her deeper into madness, making her think the virus inside her was an unborn child, and she spent her time in her cell eagerly anticipating the birth of her "baby" like an expectant mother. Eventually, the Jackal assaulted her to get the virus back, and when next seen, she was back with Carnage and worse than ever.
- Older example: The Kingpin's wife Vanessa once told him he had to choose between her and his crime syndicate. He chose her. (She gave him twenty-four hours to tie up loose ends, and he may well have killed Spider-Man, had the deadline not come right before he was about to make the killing blow.) Nevertheless, he retired with her to the South Seas. But many other crime bosses he had bequeathed his empire to didn't like having to run it without him and felt that Vanessa was the cause, so sometime later, she was apparently killed by an assassin's bullet. (She got better later.) The Kingpin returned worse than ever, not only seizing back full control of his former organization but making sure the police ended up with incriminating evidence that led to the arrest of the ones responsible for his wife's apparent death (he hadn't been fooled for a minute) a true case of a plan Gone Horribly Right.
- In Symbiote Spider-Man, after inadvertently getting an innocent woman killed during a bank robbery, Mysterio seriously considered retiring from the supervillain game out of guilt. Then Spider-Man, who was being influenced by the Venom symbiote at the time, beat the crap out of a defenseless Mysterio, which ended his thoughts of retirement then and there.
- Star Wars:
- Star Wars Tales #10, "Trooper", tells the POV account of the first stormtrooper to rush into the Tantive IV in A New Hope. Desperate to leave his backwater, dead-end planet, he murders a subversive man as a loyalty test for an Imperial officer and leaves with them to become a stormtrooper. He has witnessed horrors, committed unspeakable atrocities, and, all this time later, is beginning to lose his cold, ruthless demeanor. He wonders if he hadn't made the wrong decisions, and begins to consider jumping ship and finding the Rebel Alliance. Then Princess Leia shoots him in the face.
- Zig-Zagged in Tales of the Jedi. Jedi Knight Ulic Qel-Droma was convinced to turn on the Jedi by the Sith Lord Exar Kun and waged war on The Republic before killing his own brother Cay. As punishment for his fratricide and war crimes, Jedi Grand Master Nomi Sunrider severed his connection to the Force. After realizing the error of his ways he exiled himself to the arctic planet Rhen Var. He later ended up training Nomi's daughter Vima and found peace only to be shot and killed by a random spacer who wanted to be famous for killing one of the Republic's most infamous war criminals. However, Ulic had managed to make peace with himself and the people he hurt shortly beforehand, being redeemed in the end and becoming one with the Force like all great Jedi Masters.
- Superman:
- In Action Comics #544 "Luthor Unleashed", after a particularly ignominious defeat, Lex Luthor finally decides he can't go on like this anymore. He travels to Lexor, a planet where a single uncharacteristically good deed in his part years earlier had made him their national hero. There he settles down with the Lexorian woman he loves, has a child, uses his brilliance to help the Lexorian people, and genuinely tries to put his evil past behind him. Except... to his own chagrin, he realizes he can't. Part of it's that he can't get over his obsession with needing to defeat Superman, but more than that, he psychologically needs dogs to kick. With ancient Lexorian tech, he builds a suit of Powered Armor and uses it to become Lexor's first supervillain, the Mystery Marauder, for no other reason than to relieve his tensions by randomly destroying things. When Superman finally tracks Luthor down (ironically, one of Lex's old automatic systems had launched an attack on Metropolis without Lex even being there), Lex fights him using the armor. One of his blasts ricochets off Superman's invulnerable chest and strikes the Neutrarod, one of his inventions, destroying the entire planet, including his wife and son. Lex survives but vows to dedicate the rest of his life to a Roaring Rampage of Revenge against Superman.
- In Superman (Brian Michael Bendis), Mongul reacts to Superman revealing his identity to the world with shock and confusion as to why would he pretend to be one of the people he could’ve ruled over just like Mongul rules over his planet and begins to wonder if he himself could’ve chosen a different path… And is then immediately killed by his son, who proclaims himself the new ruler.
- Thunderbolts:
- Zemo attempted to invoke this in the original run of the series: upon realizing that individual members of his villains-disguised-as-heroes team were starting to realize that Good Feels Good and consider becoming superheroes for real, he anonymously leaked the truth about their identities to the government. This caused the entire public to turn on them, and earned them the enmity of the rest of the criminal underworld who saw them as traitors, ensuring they only had him and his larger plan to achieve any hope at freedom or survival. Unfortunately for Zemo, this backfired, as the moment they saw a chance at overthrowing him and going straight for real, they seized it.
- Though most of the original team have turned good or at least heavily considered it, it's never taken with Karla Sofen\Moonstone, as karma was bad, and her own sociopathy and greed couldn't be dropped.
- The Transformers (IDW): John Powell, the cop who holds Bumblebee at gunpoint, appears to be affected by the speech that Bee gives and may have had a Heel Realization. Unfortunately, he doesn't get a chance to lay down his arms, as Jazz blasts the officer into ash without knowing the full story, much to Bumblebee's horror.
- In Ultimate Spider-Man, Doctor Octopus refuses to help Norman Osborn kill Spider-Man. He explains that he is sick of being evil and wants to make a fresh start for himself. He also tries to convince Osborn not to kill Peter, since Spider-Man is their greatest "creation". Norman won't have any of that and kills Otto after a vicious fight.
- Usagi Yojimbo features a story involving a crooked bookie who has employed a skilled former samurai to help him run a con; they hustle wandering travelers into fighting duels with the samurai, the bookie takes bets on the fight, hyping up the unskilled traveler as unbeatable, then they split the pot when the samurai kills the traveler. The samurai begins to feel bad about this dishonest life, however, and tells the bookie he's quitting. The bookie forces him to fight one last duel to pay off a debt to him and said duel just happens to be against Usagi, who knows nothing of the con or of the samurai's intention to turn over a new leaf. They fight the duel, and Usagi wins easily, killing the samurai. The last page of the story shows the dead samurai's wife and son, unknowingly waiting for him to come home...
- In V for Vendetta, Adam Susan is shot down by the time he began to ponder about his ways and the possibility to change them.
- In West Coast Avengers, Ultron harasses Hank Pym after surviving an encounter with the Lethal Legion. Hank gains the strength to tell off Ultron and the encounter causes Ultron to rethink things. He evolves out of his hatred of Hank and humanity and resolves to be the son Hank should have had. Sadly, the previous Ultron model had returned from Secret Wars (1984) and was so aghast at the thought of a human-loving Ultron, that he ripped his head off and deleted all data on him.
- Wonder Woman (2006): When Theana, who has had no chance to learn anything other than a mass murderer due to her horrific upbringing and enforced isolation, steps back from attacking Diana after Diana is able to talk to her about her abuse and that she could be something more Theana's mother orders her executed immediately.
- From X-Men: The Blob was the oldest-running villain to lose his mutant powers during M-Day, but afterwards, the future was looking bright for him; he had become a fitness guru in Japan and would be starring in an upcoming movie filmed in San Francisco made by Kingo Sunen. However, he has since resumed his villainous ways, having been given the Mutant Growth Hormones by Mystique, restoring his powers. Clearly, super-villainy was just too much of a temptation for him.
