The Corruption / Literature

• In The Behemoth, the symbiotes are also a form of this. They are worm-like creatures possessing only a sense of touch and the ability to move slowly. When they crawl into a human body, though — through a wound, the mouth, or the ear — they merge with it, becoming a patch of mobile, bruise-colored flesh. It grants its host the ability to heal from almost any wound, seeing into the Otherworld, and gives the ability to undergo a painful and disturbing transformation into a monstrous alternate form.
• The Chronicles of Dorsa: People who have been wounded by those with shadows willingly inside of them can be possessed as well, while simply one injury opens them to it. The more who are infected, the faster the possessions happen.
• The titular Eldritch Abomination from The Colour Out of Space. It's a sentient, malevolent radiation that affects people, plants, animals, buildings and even the very landscape. Fruits and vegetables are unusually large and take on a glossy appearance but taste disgusting and are possibly also toxic. Humans affected by the Colour last quite a bit longer than other creatures, but they usually go mad and later turn into... things that definitely aren't human anymore. All affected organisms eventually grow gray and brittle as if the Colour is literally sucking out their life force, until they crumble into dust under their own weight, while still being alive and aware throughout.
• In Dis Acedia, the Poison, a substance produced by titular Eldritch Location, gives the consumer extraordinary power, but A is fueled by souls, and B eventually enthralls the user to Dis.
• In the Dreamblood Duology, once a Gatherer uses their powers to kill rather than to bestow peace, a long downward spiral of dreamblood addiction begins. If they even suspect they are emotionally unbalanced, they may ask to die.
• The Dresden Files,
  • There are the Thirty Coins, the Blackened Denarii. They are the very coins used to pay Judas Iscariot for his betrayal, and each one is now host to a bound Fallen Angel. They cannot affect the world until some mortal touches them, but at that point, a variety of unpleasantness can ensue. They are very corruptive, avatars of Hell on Earth.
  • Also, in "Cold Days", we find a much more sinister form of corruption from The Outsiders has affected some powerful magical beings.
  • The Fae Mantles also have this effect on their hosts, slowly changing them into their predecessors.
  • Black magic can have this effect on warlocks. The more they use it, the more right it feels to use it. This is particularly true with mind magic. It turns out the Council's draconian "break any of the Laws of Magic and it's Off with His Head! whether you had any way of knowing about the council or laws or effects of the spells you used" rules is because of that: use of certain spells invariably warps the mind of the user to the point that experience has told them it's "kill the user now or after they've racked up a massive body count."
• The main characters in Eden Green become infected with an alien needle symbiote that makes them immortal and turns at least one of them dangerously insane.
• The Elric Saga of Michael Moorcock demonstrates that if a human being draws closer to Chaos, their human form fades and disintegrates and they become progressively more beast-like. In the final battles, Chaos fields huge armies of beings who were once human but who are now beast-hybrids.
• The Shadow Plague from the Fablehaven series.
• In Keys to the Kingdom, if Arthur uses the Keys too much, he will be permanently transformed into a Denizen, due to "sorcerous contamination". According to the 6th book, he is past the point of no return. This could be considered Cursed with Awesome, however, considering that it helps him survive such events as getting shot in the side of the head and being dissolved by Nothing.
• The Rings of Power in The Lord of the Rings. The more you wear one, the more it corrupts you. Gollum was a normal hobbit once and the Ringwraiths were human kings. This only applies to the rings that Sauron helped make, however, and only to humans or closely related races like the hobbits. Dwarves are just too bloody stubborn to corrupt (they turn really greedy instead), while Sauron never touched the elven rings and they are thus not subject to his taint. Tom Bombadil is immune to the ring's effects because he has absolutely zero interest in anything outside his little part of Middle Earth. The Ring was even a temptation to beings like Gandalf and Galadriel, who both implored Frodo not to offer it to them. This is likely why Gandalf wanted to recruit the folk of the Shire in the first place. Hobbits seemed very resistant to the effect, possibly due to their innocent nature. The Ring's effect on Bilbo was minimal (although it did make him the longest-lived hobbit in history) and Frodo was able to successfully resist its power until the climax of the story. Even Gollum is shown still having a good side which can be coaxed out despite the extremely long time the Ring was in his possession.
• In Pact, this is what separates demons from other supernatural beings, many of whom are equally malevolent, and leads to diabolists (demon summoners) being hated and feared. Demons generate a taint, explicitly compared to radiation, which affects those around them, and in turn spreads to those that they interact with. Depending on the specific nature of the demon, the effects can be different, but they can turn animals hostile around them and drive people to violence. The taint is near-impossible to contain or avoid, so diabolists tend to spread it as they go-and whatever the effects are are always detrimental to human life, if to varying degrees.
• Paradise Lost: Gustave Doré's illustrations show Satan's progressive shift from Fallen Angel to Devil. During the flashbacks he appears like a normal angel, albeit with Devilish Hair Horns. In hell, his wings molt and become batlike, and on his way to earth he begins removing his angelic armor, eventually stripping naked. By the end, he's Jumped Off The Slippery Slope and become the traditional Big Red Devil in mind and body.
• The Parrish Plessis series has the Eskaalim parasite. It grants a bounty of powers to the infected: Healing Factor, Feel No Pain, Voluntary Shapeshifting, and more. By the time you've allowed it to advance that far, you're no longer in the driver's seat, and it's too late to do anything about it...
• In The Prince of Thorns, the Nominal Hero Jorg gets wounded with a necromancy dagger, which gives him Tainted Veins and restricted Necromantic ability. In the second book, he learns that this corruption makes him less and less human and brings him closer to being assimilated by The Dead King, the most powerful necromancer who has already subjugated most others. Then he gets a shard from a Fire Mage Gog in his body, and this also leaves him vulnerable to possession from Ferrakind, Dead King’s fire equivalent. Eventually, he manages to deal with it by over-using both of his powers at the same time, which forces the two energies to fight against each other until they are both eliminated from his body.
• Night and darkness function as this in Shadow of the Conqueror, turning any human caught in it for 24 hours or longer into a mindless creature of pure evil called a Shade.
• The Sister Verse and the Talons of Ruin has the blood of the Astral Lords, which grants anyone it's injected into rapid regeneration, but if they don't have anything stabilizing them, they are transformed into mindless bird monsters who live in constant, excruciating pain.
• The Stormlight Archive: The Parshendi forms of power. By accepting Demonic Possession, a Parshendi can assume several different forms that grant various supernatural powers (for example, stormform grants the ability to throw lightning and summon an Everstorm). But, as just mentioned, you have to be possessed by a bit of the Cosmic Principle Of Hatred to access these forms.
• In Those That Wake, hopelessness corrupts people and lets Man in Suit influence and control them.
• In Tsun-Tsun TzimTzum, the spiritual corruption of Lilith is a constant danger to anyone who tries to fight her. Falling to it completely often requires a long process of increasingly dubious moral compromises and more and more depraved self-indulgences, but it can be hurried up considerably through Black Magic that unleashes a person's worst impulses.
• Uprooted: The Wood's magic infiltrates anyone it touches to turn them into a vessel with which to bring further beings under its sway. People in its valley live under constant threat of wolf bites infecting their cattle or even pollen blowing into their crops. Just passing under the branches can turn a good person into a murderer, lying and hypnotizing and warping them into something inhuman. There's a very short window of time to heal a victim before they must be burned. Worse, the Wood is devastatingly intelligent and works deliberately to keep the two countries it borders in a state of warfare to keep them weakened while it tries to Kill All Humans.
• The Vagrant Trilogy: Infernal essence twists living flesh, dead flesh, and the land itself. However, it also goes the other way — the world itself burns infernals, which is why they have to taint the land for every step they take. The Usurper can't travel much farther north than the Fallen Palace, while the Uncivil found a way to survive with a cloak of corpses, and the First spreads himself through humans and uses them as shields.
• In Voyages of a Flying Dragon, there's the Wasteland Taint, which makes the earth itself look discoloured and diseased, and the air also gets infected until it gets to certain height above the ground. The only plants growing there become harsh and metallic, while all the animals become hollow and mindless versions of themselves, known as Demons. Humans simply get sick and die, however. Late in the first book, it is revealed that Taint is the result of Earth's power being depleted due to the industrial overuse of Elemental Bestia and is used by the Demon King to turn all other creatures against humanity, which is likely why humans don't survive to demonhood.
• Warhammer 40,000 Expanded Universe:
  • In Space Wolf, the aspirants are warned they can become "wulfen", wolf-like creatures. One does. Ragnar has to kill it. It speaks his name and dies. Only then does he learn it had been his best friend Kjel.
  • In Lee Lightner's Wolf's Honour, all the Space Wolves are threatened by its taking over.
  • In James Swallow's Blood Angels novel Deus Encarmine, many of the Blood Angels succumb to their "flaw" and begin to hallucinate that they are fighting the final battle between their primarch, Sanguinius, and Horus, and so become The Berserker; all of them are tempted by it, every fight, though Rafen notices that this time, it struck with uncommon quickness, among veterans. At the climax, Rafen succumbs to this; on the other hand, it does unlock the powers of the Spear of Telesto for him, and the daemon he fights is shocked to see that the many futures in which Rafen failed instantly vanish. Then the spear protects him. When the dying daemon unleashes it in the other Blood Angels, they terrify their enemies, who retreat although they never retreat, and the spear even lets Rafen bring back his battle brothers who had succumbed.
• Robert Jordan's The Wheel of Time novels has a few examples:
  • Mordeth lurks in the ruins of Shadar Logoth offering gifts to visitors, which will corrupt them with the genocidal madness that destroyed his city and lead them to infect everyone close to them.
  • The Dark One occasionally "blesses" some of his followers with access to the True Power, a powerful destructive force which happens to be massively addictive and drives those who use it too often violently insane.
  • While not inherently evil, saidin (male-accessible magic) was "tainted" by the Dark One in the backstory so that it can't be used without exposing oneself to the taint, inevitably driving male magic-users insane. Since magic in this setting is already somewhat addictive, and most people start off not realizing what, how or why weird things happen around them, male channellers tend to wind up nutso relatively fast. The initial taint, when there were already hundreds or thousands of active, powerful male magic-users out there, caused the Breaking of the World when they all went nuts more or less at once, and for thousands of years afterward the Red Ajah (a sect of female magic-users) dedicated themselves to hunting down and forcibly de-powering male magic-users as they manifested themselves to prevent further damage. In the course of the story the main characters manage to cleanse this taint, allowing men to once again use magic safely.

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