It looks like fire, it crackles like fire, and it even burns like fire. However, it isn't really fire.
It looks like fire because that's what the Master of Illusion wants you to see. Despite crackling, it consumes no air, burns no fuel and creates no smoke. If it generates heat or burns victims, it's because Your Mind Makes It Real. Even if it can incinerate a chair, it rarely spreads to the rest of the room. It probably deals less damage than straight-up pyrokinesis, too, though it can likely bypass resistances to fire. And a quick Tap on the Head to the creator likely puts them all out.
Also known as Marsh Lights, Fox Fire, Ghost Lights, Will O the Wisp and Ignis Fatuus, these are illusionary flames created by the supernatural, or are themselves a supernatural being like Ghosts or fairies. Living characters like illusionists, spiritualists and even supernatural martial artists can create Cold Flames through Soul Power, Ki or illusions, or by using Elemental Powers like Ice to create literal Cold Flames.
Visually, it's going to be a Technicolor Fire that isn't red-orange-yellow, usually blue or white to help denote the unnatural nature of the flames. It usually also has other, spooooky supernatural properties. Since it doesn't need a conventional fuel source, it can float around of its own accord, acting as a guide (or to get people lost) or as a Guardian Entity. Magicians may change the "fuel source" to something like poisons and use it to "burn them away", healing patients. In combat, the caster can make the Cold Flames Friendly Fireproof and not worry about harming allies. This property has the added bonus of letting casters wreath themselves in flame to look cool.
Hellfire is an inversion; fire which is even more dangerous.
Anime and Manga
- Shippo and his father in Inu Yasha can use foxfire. In that series it also has defensive properties, having protected Kagome and Shippo in the page image from a deadly attack.
- Saint Seiya: The Lost Canvas has Ignis Fatuus as an attack for the Cancer Saint, who, appropriately enough, uses Soul Power to create "soul flames" (or something).
- The flames around in Yomotsu Hirasaka are basically will o' wisps that use souls as fuel to sustain themselves. This attack is just the weaponized form of this.
- In D.Gray-man one akuma had the ability to shoot ice fire, which it used to trap Allen when he and Lenalee were fighting against him and 2 other akuma in an alleyway. Oddly, he said it burned hotter then normal fire despite the fact that it could clearly be seen freezing around Allen's leg like ice.
- Certain species of Digimon utilize this for different reasons. Some, like Gabumon and its evolutions, use it as a theme for their attacks. Others, like Kyuubimon and its counterpart Youkomon have it covering their bodies, be it as part of their attacks or simply as part of their design.
- Tomoe from Kamisama Kiss uses them, not surprising considering he is a Kitsune. In fact, he has developed a rather interesting, and rather sadistic, use for them by combining them with Baleful Polymorph. First he will transform his opponent into a game animal of some kind (a trout, an ostrich, etc...) and then use his fox-fire to cook them alive.
- One variety of mushi featured in Mushishi feeds off human body heat by appearing to its victims as an open flame. If a person huddles close to it for warmth, it saps their heat from them until they freeze to death.
- Becomes a plot point in Ao no Exorcist when Rin is trying to control his blue Hellfire so that it only burns what he wants it to. He eventually succeeds. Interestingly, Rin and Yukio appear to be invulnerable to each others' flames.
- Sheikh Suleiman in the 2009 Clash of the Titans could heal wounds with his flames as well as burn enemies.
- Also known as Ignis Fatuus (Latin for "foolish fire") and "jack-o'-(the)-lantern" (until the latter term highjacked the function formerly held by "turnip ghost").
- Kitsune in Japanese folklore have this ability.
- Most versions of Tam Lin require the heroine to hold onto her lover in some form that's burning, trusting that he will not hurt her. In the related story "The Faerie Oak of Corriewater", when the rescuer takes fright and lets go, she does burn to death, implying Your Mind Makes It Real.
- In Terry Pratchett's Thief of Time, Kaos has a sword which generates Cold Flames. Literally. The flames in question freeze the air.
- In Quest for the Fallen Star, Earthpower manifests itself as green flames (or yellow ones, if Ill-creatures are using it). Subverted in that these can actually set stuff on fire.
- In Robert E. Howard's Conan the Barbarian story "Gods of the North", Ymir uses this.
The girl's ivory body was suddenly enveloped in a cold blue flame so blinding that the Cimmerian threw up his hands to shield his eyes from the intolerable blaze.
- Jarlaxle from the Forgotten Realms possesses a wand that shoots out illusionary fireballs. What makes them different from other illusions is that Jarlaxle practiced with it so much that it was almost indistinguishable from the real deal, to the point where several goblins actually died from it.
- In the Coldfire Trilogy, the Hunter is skilled in the creation and usage of "coldfire" which is as cold as real fire is hot. He warns Damian that it is just as volatile and dangerous as true fire. The Hunter wields coldfire because part of the price he paid for his form of immortality is that he can no longer manipulate normal flames.
- An in-universe history book in Harry Potter references wizards using a spell to turn fire cold to survive burning at the stake.
- Mages who can control Fire in Mercedes Lackey's Elemental Masters books can call up illusory fire as well as the real thing.
Live Action Television
- In Kamen Rider Ryuki, Evil Counterpart Ryuga's Finishing Move has his Contract Monster launch a blast of black flames that freezes the enemy's legs to the ground, holding them in place so Ryuga can deliver a flying kick to them.
- Older Than Feudalism: The burning bush in The Bible.
- In the Qu'ran and Jewish legends, when Abraham was burned by Nimrod in the stake, he prayed to God and God made the fire cold. The same thing happens also in The Bible when three righteous people are cast into a fire.
- Magic: The Gathering has both Will O Wisps as enemies and one rare spell called Ghostfire, which deals Non-Elemental damage... and is invisible.
- Exalted (natch) has Pyre-flame, one of the five Corpse Elements of the Underworld. It's green, burns through anything despite lack of fuel or oxygen, and behaves like a viscous liquid. It also melts away instantly in sunlight—which isn't much of an issue in the Underworld, which has no sun.
- Orpheus gives us the Wisps, ghosts/projectors who have the innate ability to produce ghostly flames. Not only do they do a number on ghosts, they can also be used to distract mortals.
- The Ghostbusters Tabletop RPG classifies this as a Class 1 ectoplasmic manifestation.
- In Vampire: The Masquerade, making illusory fire is one of the favored tricks of the Ravnos clan.
- Faerie Fire in Dungeons & Dragons wraps the target in flames - harmless, too dim to blind, but outline prevents concealment via invisibility or Blur spell, let alone normal darkness.
- Forgotten Realms introduced Continual Faerie Fire - a greater area-affecting version.
- Will o' Wisp is an attack in Pokémon, which causes the burn status and nothing else. No other attack does that as its main effect, only as a side effect.
- Will O'Wisps are medium-level enemies in The Elder Scrolls IV: Oblivion.
- Shivering Isles gives us The Cold Flame of Agnon, a mystic orange and green fire that can be literally worn, is kindled by the willing self-sacrifice of two Daedra and is used to light the Great Torch of New Sheoth.
- The Legend of Zelda Ocarina of Time features magical blue flames which can be stored in a bottle. The potion shop clerk says you can use them "to feel refreshing coolness", but their only real in-game purpose is to melt the red ice you find in some areas.
- Spirit Tracks brings the blue flames back, and they freeze stuff - their first uses are to make the boomerang burn with them to freeze paths on water.
- In World of Warcraft Lord Marrowgar, the first boss of Icecrown Citadel, spawns lines of blue fire known as Coldflame that deal frost damage to anyone who stands in them.
- Mages can also cast Frostfire bolts, which act as either frost or fire depending on which the target is more vulnerable to.
- Most of the fireball attacks in Street Fighter. Even Dhalsim's fire blasts are illusory.
- Suika Ibuki from Touhou has this in the fighting games in the form of an alternate special attack. The name of the attack? Ignis Fatuus.
- In Chrono Trigger you have the Triple Tech Frost Arc/Arc Impulse, with Crono Frog and Marle, it involves Marle the ice mage causing Crono's sword to burn with a weird coloured flame. Said flame is from the Ice2 spell.
- A creature made of this shows up in a late 2010 story arc in El Goonish Shive. Justin and Elliot note his lack of actual heat.
- In Gunnerkrigg Court, Antimony Carver primarily uses her blinker stone to produce flames like this, even being capable of starting fires that provide heat and light while being undetectable to electronic sensors. Possibly also a power of the fire elementals that Annie is apparently descended from.
- How to Kill a Mockingbird: The mockingbirds are all constantly on cold fire, represented as blue flames.
- The girl at Whateley Academy in the Whateley Universe even calls herself Foxfire and has a fox kit familiar.
- The Tick: This was one of the inventions showcased at the Mad Science Fair in "The Tick vs. Science".
Scientist: Look - the marshmallows aren't even roasting. They remain at a comfortable 68 degrees.
- In Australia we have the Min-Min Lights, little balls of cold fire that scare the bejeezus out of people... Explorers and such used to believe they were spirits. They're just lights refracted around the curvature of the Earth. That's how flat parts of Australia are.
- The Doing In the Wizard explanation for marsh lights is that they're actually caused by phosphorescent gases escaping from the marsh.
- St. Elmo's fire.