People going mad from the revelation in anime and manga.
- In 20th Century Boys, approximately 2/3 of the people who complete Friend's VR, which purportedly reveals his face, are Driven to Suicide. It's not his face, it's Sadakiyo's—specifically it's his adult face on a child's body. In a simulation that is otherwise completely indistinguishable from reality, it drives people crazy simply because of how wrong it looks.
- More or less every single Tipharian in Battle Angel Alita that learns "the secret of Tiphares" (Tipharians undergo a special ceremony at the age of nineteen. During this ceremony, the brain of the Tipharian is replaced with a computer chip) is driven insane. Most commit suicide.
- Alita is a citizen of Tiphares thanks to Desty Nova. Heroic BSoD time!
- The events of the Eclipse in Berserk took a horrible toll on the mind of Casca, who not only lost every one of her men, including Judeau, to things out of nightmare, but was raped by the very essence of evil itself in the form of the fifth member of the Godhand, Femto — who used to be Griffith, one of the two most important men in her life — right in front of Guts, the man she loved. The trauma of the experience rendered her mute, amnesiac and insane, essentially turning her into an Empty Shell of her former self. It doesn't help one bit that Guts left her for two years to pursue vengeance against Griffith.
- The poor mother who gets put to the torture by Mozgus to "expiate her sins" during the Conviction Arc is later seen back among the refugees having gone completely insane and clutching the corpse of the baby she had gone through hell for.
- The reason Schwarzwald from The Big O goes mad and decides to destroy Paradigm City is because he figures out the show's Ontological Mystery (or at least part of it... it's a big mystery).
- In Chrono Crusade, Aion has a tenuous grasp on his sanity after he's Mind Raped by Pandaemonium and discovers the Awful Truth of his origins.
- Jeremy has one of these in A Cruel God Reigns after he finds his mother's diary detailing that she knew Greg was raping Jeremy, but did nothing. This leads to his Driven to Suicide Bungled Suicide just as he is going to confess to killing Greg to Ian.
- Danganronpa 3: The End of Hope's Peak High School: In Future Chapter, Kazuo's reveal of the attacker being technically everybody has this effect on Kyousuke, causing him to become singularly obsessed with ending the game by any means necessary... even if it means killing everybody.
- Digimon Adventure 02: Certainly not the only factor in his descent, but his visit to the Dark Ocean a perpetually dark realm, populated by various Lovecraftian horrors and where Love and Hope are a foreign concept, was definitely the Straw that Broke the Camel's Back for Ken Ichijoji.
- In Fantastic Children, scientist Dr. Radcliffe became obsessed with unraveling the mystery of the Children of Befort. Needless to say, the more he found out, the madder he went. He could have been saved a lot of suffering if he knew that his theory was actually as far from the truth as you could get.
- In Fullmetal Alchemist, it's strongly implied, and possibly outright stated, that the experience of going through the Gate is so "awful" that even if you did manage to survive through the pain of whatever it took from you, you could wind up a vegetable.
- Isaac McDougal, a.k.a. The Freezing Alchemist, from Episode 1 of Brotherhood went totally off his rocker when he uncovered the country-wide transmutation circle conspiracy, and decided to remedy the problem by attempting to reduce Central to a frozen pile of rubble.
- Towards the end of Gankutsuou Heloïse Villefort, who seems perfectly normal in her first appearances, is revealed to actually be a murderous woman who's out of touch with reality. When her husband tells her to her face that she's just a murderous Bitch in Sheep's Clothing, and reveals that he knows she's been trying to kill him and their daughter Heloise collapses to the floor, finally giving into her insanity. Her husband then has her committed to an insane asylum for the rest of her life.
- Every so often Ghost in the Shell: Stand Alone Complex uses this trope to great (chilling) effect. For example, in the episode entitled "Not Equal" an American Special Ops soldier is reduced to a gibbering, suicidal shell of a man after seeing the memories of the experiences that aged a young girl into an old woman in the span of 16 years during her time as a prisoner of a paramilitary group.
- In the Halo Legends segment Homecoming, a few of the escaped Spartans find out they've been replaced with clones, leading a few to commit suicide.
- What happens to Kurumi's friend Kaafai from Haou Airen when he's Forced to Watch as Hakuron rapes Kurumi. This is why he shoots Hakuron to death in the end.
- Russia from Hetalia: Axis Powers during the Bloody Sunday strip, in which he snaps and starts to mow down his own people on the grounds that "they're not really Russians if they don't love me."
- In Hunter × Hunter, the sheer intensity and strength of Neferpitou’s and Meruem’s auras can be so overwhelming for a regular Nen-user, that even a momentary exposure to it can have severe permanent psychological and physiological consequences. Knov, for instance, who was specifically picked up for the highest-threat and highest-difficulty level mission against Chimera Ants, became almost completely demoralised after seeing just the brink of Neferpitou’s aura at close range and soon after lost almost all hair on his head. Similarly, Welfin rapidly aged and his fur fell out when he felt the King’s Killing Intent focused on him.
- In Monster after Nina recovers all of her memories and realizes that the memories her evil twin brother Johan thinks are his are really hers (it's complicated), she nearly commits suicide. Thankfully Dr. Tenma intervenes just in time to avert a potentially HUGE Tear Jerker.
- Naruto:
- Sasuke, understandably, does not react well when he finds out the truth about Itachi. Thankfully, after 200 or so chapters, he gets better (well, or so it seems).
- Likewise, Madara Uchiha went mad after reading deeply into the Uchiha Tablet and discovering that their war-torn world has always been such and that it only became worse once a princess sought to end all conflict by stealing Chakra from a God/Eldritch Abomination and becoming a goddess herself. Which was exactly what Black Zetsu intended when he rewrote the tablet. Madara was driven mad by a lie.
- Towards the end of Neon Genesis Evangelion, Shinji Ikari finds out that Rei Ayanami, one of his closest confidants, has died and been replaced by a clone, and later still he deduces that there is definitely a connection between her, his dead mother, and the weird presence in Eva Unit 01, and these revelations does indeed shake his already fragile psychological stability quite a bit. It finally comes to a head in The End of Evangelion when the ritual to awaken Lilith/Rei Ayanami reduces him to a fit of shrieking omnicidal insanity. It didn't help that he had just seen Asuka's torn-apart remains only about a minute earlier.
- Suzu in Peacemaker Kurogane becomes Ax-Crazy and a Depraved Homosexual after finding his beloved master dead, and being raped by an old man.
- Perfect Blue: In the anime's denouement, Rumi is permanently delusional and institutionalized.
- Mewtwo from Pokémon: The First Movie goes off his gourd when he's basically told that his purpose in life is just to be a science experiment and/or a weapon and nothing more to those who created him. As a result, he psychically nukes a lab and a Team Rocket base, kills the scientists who brought him into being, almost kills Giovanni, and decides to make himself judge, jury and executioner to every human and Pokémon on the planet. Ash's desperate attempt to stop the fighting between the clones and original Pokémon is enough to bring Mewtwo back to Earth and question his initial belief on humans.
- Puella Magi Madoka Magica: Happens to Sayaka Miki, and Mami Tomoe from the third alternate timeline. Sayaka starts losing it as she realizes that not only does no good deed go unpunished, but being a Magical Girl is NOT sunshine and rainbows. She ends up becoming the witch known as Oktavia Von Seckendorff since among other things, she brought hope to others only to lose herself to despair and her wishes weren't as selfless as she believed; the third Mami goes insane with grief after the Sayaka of her continuity also becomes Oktavia (probably in similar circumstances) and is killed by Homura, since she cannot handle the Awful Truth that being a Puella Magi means she will eventually become a witch; she kills Kyouko and gets ready to kill Homura, so Madoka has to Mercy Kill her.
- And in the backstory of Kyoko Sakura, this happened to her father, when he found out that Kyoko used her Selfless Wish to brainwash people into following him. His mind splintered so badly that he went the Pater Familicide route, with Kyoko as the Sole Survivor of the Sakura clan.
- Occurs to one of the astronomers in Remina when he realizes that Remina's a sentient Planet Eater...and it's headed for Earth.
- In Rurouni Kenshin Soujiro goes temporarily insane when he realizes that he did regret killing people despite clinging to the words of his Evil Mentor: -> "If you're strong you live. If you're weak, you die." It doesn't help that the people he regretted killing were his Abusive Parents or that he'd been a Stepford Smiler so long that every other emotion was completely suppressed until then. To top it all off it was Kenshin's words that caused this. It eventually leads to Soujiro's Villainous BSoD.
- School Days' Kotonoha and Sekai. Both are dumped by a Jerkass Makoto Ito and have realized that he's also screwed around with their best friends. Kotonoha's eyes turn dark around the later half of the anime, especially after it's implied that Makoto's friend raped her.
- Space Pirate Mito: Masatsuki Nenga goes insane when he comes to the realisation that his "Justice" is nothing more than a tool of oppression (one that has no issue shooting down a "mob" of villagers, men, women and children) used by a pretender to the throne. This leads to about two episodes worth of him screaming "I AM JUSTICE!" at the top of his lungs whilst firing his gun like the lunatic he is. This would be fine all in all, but the guy doesn't look older than 12.
- Ralph Werec of Str.A.In.: Strategic Armored Infantry went from perfect soldier to traitorous Omnicidal Maniac when he saw that his people had created the Humongous Mecha he was piloting by killing harmless little alien girls for their Psychic Powers. However, though his reaction is understandable, when one of the sort-of-survivors shows Sara the story in a vision, she keeps her own sanity. Ralph also got sucked into a dimensional rift that gave him terminal cancer directly after said vision.
- Tokyo Ghoul:
- Mutsuki breaks down into hysterical laughter and undergoes serious Sanity Slippage after seeing Torso's mutilated body done at his hands and realizing the full scale of his past crimes that he had long tried to bury in his mind.
- Yamori inflicts a series of brutal tortures on Kaneki: first cutting off his fingers and toes (they grow back) over and over for days, then stuffing a live centipede in his ear and duct-taping his head so that it tunnels into his brain. Kaneki starts to laugh hysterically, but what truly shatters him is Yamori giving him a Sadistic Choice: choose one of a mother and child pair (two lovers in the anime) for Yamori to kill in front of him. Kaneki breaks down weeping and begs Yamori to kill him instead, but Yamori loses his temper and kills both victims. One after another, these tortures snap Kaneki's already rather fragile mental state like a twig, causing him to assume the role of a ruthless Anti-Hero and suffer further mental issues throughout the series.
- During Itsuki Marude's confrontation with Yoshitoki, Matsuri heard the gunshot from another part of the ship. When he went to investigate, he came across the aftermath of the battle and discovered his father's corpse. Barely maintaining his composure, he radioed Urie to report the commander's death at the hands of an "unknown assailant." He falsely reported that Marude had committed suicide, and then collapsed to the ground after ending the transmission. Weeping hysterically, he spoke in an effeminate manner and swore revenge against Marude for his father's murder. His insanity is further shown in chapter 100 where he tears his clothes off until he's naked in front of a window in his office and flamboyantly declares his love for Urie. This occurring not too long after his despair at having lost his father.
- Big Bad Millions Knives from Trigun has this as his manga origin story. (In the anime he just decided Humans Are the Real Monsters for semi-logical if not terribly extreme reasons, and then went Evil Plan on them and his brother. In the manga, he was a sweet boy who snapped after discovering the Awful Truth—that there had been an 'Independent Plant' born before him and his brother, and the crew had studied her right to death.
- Notably, if you didn't already know who was going to grow up to be the villain, it would look like Knives handled it better than Vash. They both locked themselves in and attempted to starve to death together, but after Rem broke in and saved them it was Vash who did the Laughing Mad and Humans Are Bastards and hysteria, and Knives seemed...perfectly okay. He saved his freak-out until after he'd set up all the colony ships to crash.
- On Tsukuyomi: Moon Phase, Kouhei experiences temporary madness after his new power lets him see Hazuki's true form, after which he temporarily becomes a trembling wreck who screams like a madman every time he sees her, he eventually gets over it though.
- In Yuki Yuna is a Hero, after Togo learns what the world is like beyond the barrier created by the Shinju-sama, and that the heroes fight against the Vertex will never end, Togo decides it would be better to end the world on the spot rather than continuing to fight an uphill battle that would inevitably end in the remaining humans of Shikoku dying anyway.
- YuYu Hakusho, of all series, has this happen to Sensui in his backstory. Not from any eldritch lore, though, but from simply seeing how horrible people can be—shattering his belief in black and white morality by witnessing the torments sadistic humans inflicted on demons for fun, leaving him an omnicidal maniac. Chapter Black is also noted to be able to force people to go mad from the revelation. It's a compilation of every terrible thing humanity has ever done in loving detail. This is implied to be partly a supernatural effect. It should be noted this is a case where a partial revelation has this effect: there's a Chapter White, a compilation of every good thing humanity has ever done in equal detail. The two are meant to be viewed simultaneously, never seperately.
