"You dare interrupt me! Only I interrupt me! Like just then. I'm speaking with someone! We'll talk later. Or not. When is later, exactly? Not now, I'm sure of that."
—Sheogorath, The Elder Scrolls IV: Oblivion
This God isn't Evil in either sense, or even a Jerkass God. It is simply insane. Its mad throes create and destroy in equal measure, leading to untold chaos. That there is a universe at all is usually due to it being Sealed Evil in a Can, dormant, or so random that it's been less destructive over the past few aeons.
It might even be posing as a sane and good god because it has momentarily grown Bored with Insanity. Of course, that doesn't usually last, as sanity tends to bore it greatly as well.
Expect the Nietzsche Wannabe to consider it Above Good and Evil, or that it follows Blue and Orange Morality that anyone can understand... if you just gaze into the abyss of madness long enough. If especially mad and powerful, it may also be an Eldritch Abomination. It may not cause insanity or revulsion to observers, but that's usually iffy, and depends on if it has enough presence of mind to take on A Form You Are (at least mildly) Comfortable With.
Contrast A God I Am Not, where a god-like being refuses to be called a god to avoid something like this occurring.
Anime and Manga
- Asura from Soul Eater, a demon god who went mad with fear and infects the world with his insanity merely by existing.
- Later chapters imply that all Eight Warriors from the days of old each represent some form of madness, like Shinigami representing madness from Rule of Law.
- The Joker, in the Emperor Joker series, tricked Mr Mxyzptlk into giving up the lion's share of his power, and he used it to rewrite the entire universe in his image. In the end, only his obsession with Batman (and his inability to keep his imagination from conjuring his own worst fears) stopped him (with a helpful nudge from Superman).
- The Christian God of Hellblazer is claimed to be this by the First of the Fallen, saying he "found the Great Redeemer squatting in a corner of Eternity. Clutching his genitals... and drooling." Not that he's the most trustworthy of fellows.
- The Christian God of The Chronicles of Wormwood. The only thing he does throughout his entire appearance is float in the air, grunting and constantly masturbating, and in "Chronicles of Wormwood - The Last Battle", Jesus reveals that when he ascended to Heaven after his resurrection and went to see his father, he found him making little toy houses out of his own feces.
- The Writer from the Good Apollo I'm Burning Star IV Volume One: From Fear Through The Eyes of Madness arc of the Amory Wars.
- In the American Sonic The Hedgehog comics, any echidna who absorbs too much Chaos energy is transformed into the demigod Enerjak, and is driven mad in the process. Dimitri and Knuckles have both suffered this at different points, and an Alternate Universe features a version of Enerjak-empowered Knuckles who's pretty much destroyed the whole world.
- The cover of Green Lantern issue #6 from the nineties series describes Appa Ali Apsa, the Old Timer, the last Guardian, this way. It is a reasonable description, given his power at that point.
- The Supreme Being of Space Sector 3600, the god TDHD, has gone utterly mad, and was for some time walled off from reality by the Guardians of the Universe.
- Delirium from The Sandman, what with her being the Anthropomorphic Personification of madness.
- Thanos is occasionally referred to as The Mad God.
- The protagonist of The Gods Must Be Crazy assumes this is why a Coke bottle falls out of the sky into his primitive village, bringing strife to the community. To them, it's a cruel trial that can only have been masterminded by a malevolent and crazy god.
- Loki in The Avengers seems to have a bit of this—he's more than a little unhinged after the events of Thor (namely falling through a portal into the abyss of the universe), and abuses his powers as the God of Mischief to terrifying effect.
- Monstrous Regiment: Nuggan, despite being dead, manages to effectively behave in this way, forbidding babies, the color blue, and other absurd things.
- Azathoth, the Blind Idiot God gibbering at the chaotic center of Creation (his creation) in the Cthulhu Mythos. Note however his being a 'god' is debatable, as it is with practically all of Lovecraft's more tremendously powerful entities.
- Nalar, Big Bad of the Riftwar Cycle is sometimes called the Mad God, though it's implied that even if he was sane he'd still be a God of Evil.
- In The Belgariad we get two Mad Gods: Torak is essentially this plus God of Evil and Mara went crazy after his people were wiped out in a war, casting illusions on the entire country that drives
everyonemost people who don't have magic powers or divine protection who dare to make even one step into his country insane.
- The Crippled God of the Malazan Book of the Fallen was a deity who was forcibly dragged from his own reality and into this one. His body torn and ravaged by his arrival, which shattered a continent, he was chained and locked away to try and prevent his increasingly corrupt powers from infecting the world.
- The Faerie queens of The Dresden Files don't have a great track record for sanity. However, Word of Jim points out that since madness is defined as being out of touch with reality, you can't really call someone who can warp reality to their will mad.
- Most of the deities featured in American Gods are quite stable... except for Horus, he's crazy. Fortunately he's not really in a position to do anything damaging.
- Harlan Ellison's short story "The Region Between" proposes that all life in the universe is formed from fragments of a god like this, which destroyed itself in its own madness. In the end, it's reconstituted just long enough to kill itself for real by ending the universe.
Live Action Television
- Bobo is mistaken for this by the ancient Romans in Mystery Science Theater 3000. Oddly, he's only really "mad" in the sense that he fights lions in the gladiatorial arena for fun- which admittedly is a bit much since the other local "Gods" (Pearl and Brain guy) spend most of their time not doing anything even remotely that impressive.
- In the Mirror Universe of Hercules: The Legendary Journeys, Zeus went mad from the strain of building "The Labyrinth of Eternal Memory" for his newborn son Hercules. With the king of the gods insane and the rest of the pantheon thrown into chaos, the stage is set for this version of Hercules (known as "the Sovereign") to Take Over the World and hatch a scheme to become the new ruler of Olympus.
- Forgotten Realms: Cyric is much more competent sane than insane. A lot more pragmatic, too. But still -very- evil.
- The Chaos gods of Warhammer Fantasy Battle and Warhammer 40,000. Composed of every mortal thought and emotion, magnified and taken to the extreme by their concentration in the warp, they are the essentially personifications of Rage (Khorne), Despair, (Nurgle), Desire (Slaanesh), and Scheming (Tzeentch). Spreading their emotions and philosophies in the real world through mortal and daemonic followers, they are well aware that true victory for any of them (or all of them) would destroy what keeps them existing, yet they pursue it anyway.
- Tzeentch is mad even by Chaos standards. The Chessmaster par excellence, it constantly weaves extremely complex schemes that more often than not contradict each other, that ultimately have no point at all, and in succeeding with one it foils countless others (and so on ad infinitum). Indeed, to Tzeentch scheming is a purpose in itself, as if any of its big plans were to ever succeed it would cease to exist.
- The C'tan Outsider in 40K, one of the Necron star gods who was tricked by the Laughing God of the Eldar into consuming others of its own kind, which eventually drove it insane.
- The Primordials of Exalted, the creators of the universe, are quite insane by human standards, even the relatively nice ones like Gaia and Autochthon. The developers have even used human mental disorders as metaphors for how each Primordial views the world—Oramus is schizophrenic, Malfeas is solipsistic, Autochthon is autistic, She Who Lives In Her Name is obsessive-compulsive, and so on.
- All of the Madlander deities in GURPS Fantasy II: Adventures in the Mad Lands. Togeth, god of the Togethians, may be one too - the magic he grants to worshipers is extremely random, though at least it's always beneficial, unlike what the Madlander gods tend to do.
- Dungeons & Dragons 4e core setting labels pretty much all the chaotic evil gods as this, mainly Tharizdun, Lolth, and to a lesser degree, Gruumsh.
- Ragnaglar from RuneQuest is the Mad God.
- The Mad Gods from Witchcraft, natch- every single one is a Cosmic Horror from beyond our reality, whose understanding of it is terribly limited; so when they manage to intrude here (and before, even), they begin to reshape it to a form they prefer. Which needless to say is very bad news for the natives (even including the angels and demons).
- The Mad God from the Fighting Fantasy gamebook "Portal of Evil." Provides the hero with a helmet that has mirrors attached to it. The helmet turns out to be useful later on when revealing to The Dragon what a monster he has become.
- YHVH in the Shin Megami Tensei series, according to Word of God. True, he does commit acts of hideous evil, but the cause is because the universe itself is fundamentally broken in some way, and the Abrahamic God being an insane puppy kicking asshole is merely one of the most blatant symptoms of how the universe itself screwed up.
- Sheogorath, the Daedric Prince of Madness from The Elder Scrolls. His condensed title, referred to by the Dark Seducers, is "the Madgod." In other words, he's not just a Mad God, he is the god of madness, and the insane are his subjects.
- In Morrowind, everyone who has ever touched the Heart of Lorkhan has gone mad (maybe not Vivec, though). Sotha Sil has retreated into a clockwork city of his creation (in a world where clocks have not yet been invented), Almalexia tries to murder you, and the Big Bad Voryn Dagoth, your past life's lackey gone bad, is repeatedly stated to be mad and it shows through his minions.
- Shivering Isles reveals that the Daedric Prince of Order Jyggalag is a Mad God. The other Daedric Princes cursed him because they feared his growing power, and he now suffers from a split personality. His other personality is Sheogorath. In his own words, he is a "broken ruler, of a broken realm". The Greymarches are merely his attempts to restore his Realm whenever he briefly regains his right mind. "Killing" him at the end of the Shivering Isles questline cures him of his madness, leaving him free to wander Oblivion to rebuild his powerbase while he passes on the mantle of the Prince of Madness to the player character.
- Linleys Dungeon Crawl: "Xom thinks this is hilarious!"
- In Pokémon Mystery Dungeon Explorers, Dialga is a benevolent enough god, but for most of the pre-credits storyline, he's going insane and changing into Primal Dialga.
- Jubileus The Creator of Bayonetta goes insane once the Left Eye is lost, throwing the Balance Between Light and Darkness out of alignment. Whether Jubileus was good or evil to begin with isn't clear, since in this Crapsack World Dark Is Evil, Light Is Not Good, both Angels and Demons qualify as Eldritch Abominations and humans are, for the most part worldly or gullible idiots.
- In EarthBound, the player is trying to prevent the world's destruction at the hands of Giygas, a powerful psychic entity from the future. Their efforts apparently spook him so badly that he overdoses on evil energy before the final confrontation, turning him into a god (of sorts) and destroying his mind. He rambles insanely during the last fight, and seems barely even conscious enough to know who he's fighting.
- Majora of The Legend of Zelda Majoras Mask. Very little is known about Majora, except that he goes completely apeshit and tries to destroy the entire world by crashing the moon into the earth, cuz he's freakin' god, and he feels like it.
- In Eternal Darkness Chattur'gha and Ulyaoth are not particularly right in the head, at least not to human senses, but Xel'lo'tath is the only one whose very presence (and those of her troops) drives people mad; she hears voices in her head, and you hear voices in her head too.
- Kefka Palazzo becomes this in the second act of Final Fantasy VI.
- Tarjan from The Bard's Tale Trilogy. He's even called the Mad God.
- Malygos, the Aspect of Magic from the Warcraft games used to be a fun-loving dragon who ruled over magic. But after his entire people, including his mate and children, was slaughtered by his best friend with a weapon he helped create, he completely lost his mind. He hid for millennia in a cave and was prone to killing anybody who approached him. It's only after being given a new flight that he starts to become sane again... at which point he decides to declare war on every magic user in the world (that is every single faction of the game, including the other dragons which helped him and the mortals who did his job for 10,000 years).
- Neltharion aka Deathwing is this and a God of Evil. That's what happens when a godlike dragon is Mind Raped by a cabal of Eldritch Abominations. Deathwing's own power tearing his body apart (to the point that he has to have metal plates riveted to his body just to keep it together) leaving him in constant agony probably didn't help his sanity either. In the finale of Cataclysm being blasted by the Dragon Soul makes him lose what little control he had over his own power. His body falls apart and the last vestiges of his sanity go along for the ride.
- The main villain in the flash game Realm of the Mad God is one of these.
- Yahweh in The Salvation War is arbitrary, narcissistic, throws temper tantrums when things don't go the way he wants or expects, and seems somewhat... impaired at times. Then again, he may not be an actual, literal god in the sense that's used here.
- My Little Pony: Friendship Is Magic:
- Nightmare Moon resulted from Luna resenting the ponies who rejected her night in favour of Celestia's day, her jealousy (and a bit of corruption by dark magic) consuming her until she enacted eternal night in a stubborn attempt to force the ponies to love her. She seems completely unaware that this would kill all life in Equestria.
- Discord, spirit of chaos and disharmony, whose body even looks like someone chopped up half a dozen different creatures, lost most of the pieces and tried to stick them back together. As a Reality Warper of near-unlimited power, within a day he turns Equestria almost literally upside down, with days and nights lasting less than a minute, gravity turned off in places, and at one point he drinks a glass of chocolate milk (not the milk, the glass) and throws the milk away where it explodes.
- He died due to people only really believing in the list of things he'd forbidden, so since Gods Need Prayer Badly, all that was left of him was a voice forbidding random things.