Supernatural Sensitivity

In any setting where there are people with uncommon powers, be they magical, psychic, or ki-based, it's a common trait for those blessed with such abilities to be able to sense it in others. This often results in simply having characters remark of one another: The Force Is Strong with This One. But sometimes, they sense more than the sheer amount of power and can actually detect fine details in what's going on. There are two basic ways this works:

Activity Detection

Characters can sense when others are using magic, and perhaps exactly what they're doing. Often tied to vision or hearing, but could also just be some sixth sense unrelated to those possessed of normal people. The signs of magical use are proportionate with distance, and by the degree of power being emitted. There are probably tricks to avoid detection or damp the signs of use, and other tricks to see through those.

Residual Detection

Use of magic leaves signs which can be sensed by those with the right gift. Any place where magic has been performed, and any object or person under the effect of a spell will have a residue that fades with time. The amount of detail which can be gleaned from this method varies. This is common in settings which have a Background Magic Field.

The sensitivity of magic-users to one another is important in the development of a magic system. It acts as a limiter on the more powerful users in High Fantasy: The mighty wizard could wipe his current foe off the map with ease, but doing so would attract the attention of much darker and stronger forces. Thus, he has to resort to more subtle and indirect magics, and save his strongest stuff for true emergencies. Sensitivity also plays a key role in unraveling a plot, as the characters check residues and enchantments to try and uncover who did what long after the fact.

Often tied to Aura Vision and the use of this might lead to a Magical Sensory Effect for the user. See also The Empath, who may have these abilities, Psychic Radar and Detect Evil. Not to be confused with Super-Senses.

Compare Magic Is a Monster Magnet, where possessing or activating powers attracts the wrong sort of attention. A subtrope of Meta Power.

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Examples:

Anime & Manga

• In Black Clover, Yami teaches Asta to sense Ki in order to make up for his lack of mana. This allows him to find his target in the middle of a battlefied filled with smoke and residual mana, where any other mage would be blind.
• Bleach: Powerful spirit creatures such as Soul Reapers and hollows can detect the use of spiritual pressure (spirit energy) a considerable distance away.
• Kari Kamiya in Digimon Adventure displays this throughout the series, being sensitive to the presence of Digimon, their emotions, and the general state of the Digital World; she usually needs to be in the Digital World herself for that last one to work, though. It's never explained in-series why she's the only one of the Digidestined to display this ability, but one of the novel adaptations states this is why her crest is "Light", rather than an interpersonal characteristic or virtue like the others.
  • In Digimon Adventure: (2020), her powers are boosted to the point where she's fully aware of major events in the Digital World even if she's still on Earth, hence why she thanks Tai in an early episode despite him never even hinting at his actions.
• Fighters in Dragon Ball Z can detect the use of ki from others, as well as potential, though that can also be concealed. Freeza's army cannot, but they have special sensors for that. They also apparently had never encountered anyone capable of either feat, because Vegeta and Nappa are surprised by it; Vegeta eventually destroys his sensor, since it's useless against those foes and he's starting to learn how to sense ki, anyways. Later, during the series' stint in Namek, he keeps perfecting that technique. He detects Krillin and Gohan, who are hiding a dragon ball from him, but a whale-like thing jumps up nearby and he reasons he must have detected that. He also starts learning how to conceal his ki, keeping it nearby his former power level, to get the drop on the rest of the army and the generals.
• Frieren: Beyond Journey's End: Magic-detection, and the ability to prevent it by suppressing one's mana, are frequent plot points.
  • Mages who hunt demons have to learn to suppress their mana signatures because demons can detect it. Frieren is so good at it she gives off virtually no mana signature at all; ditto her apprentice, Fern. This allows them to blindside the demons trying to destroy Graf Granat's city.
  • The first test of the first-class mage exam is to catch a bird called a stille and return it to the proctors alive, which in addition to having Super-Speed, is repelled by mana signatures of nearby creatures. Frieren and her assigned party members exploit this: they freeze the lake at the center of the testing area, then imbue every pond and puddle they can find with mana in order to herd a stille to a target watering hole so she can catch it.
• Detecting the aura of Youkai is a useful ability in Inuyasha, common to Youkai themselves, Hanyo like Inuyasha, and to ki using humans like Kagome and Miroku. Even exterminators like Sango could sense it to a lesser extent. There was an old exorcist who was completely insensitive to youki, which turn out to be rather helpful since it didn't affect her either.

• In That Time I Got Reincarnated as a Slime, all monsters have Magic Sense, which detects nearby sources of magic, gauges Power Levels in individuals, and can be used to communicate telepathically.
• In Yozakura Quartet, half-youkai can sense youkai energies, including in one another. "Uncle" Jinroku can also sense the dragon pulse in the earth to help others fight fallen youkai and to find good clay and bamboo.
• Fighters in YuYu Hakusho usually can only tell how much energy is being put out in a given direction and by whom, but in the Dark Tournament arc Kurama and Hiei are able to sense Genkai's death.

Comic Books

• Zatanna: Everyday Magic: When Zatanna is coming back home after her tour, she feels an odd supernatural chill near the entrance. She dismisses it at first, but when she finds out Constantine is hiding inside to protect himself from a Trader demon, she figures it was the demon lurking nearby that she felt.

Fan Works

• A Certain Magical Friendship: Context_SHIFT: The first chapter had Index wonder at feeling sudden, large, amounts of magic:
  Index jerked awake as she felt powerful mana collect right underneath her. Her 'spell' was powering up?! Where was it getting mana from? Had she tapped into a ley line or the Fung Shei of the area purely on accident?
• Child of the Storm: aside from the Sight, which most Wandless practitioners can use, any sufficiently powerful or skilled witch or wizard can sense a general build-up of magic, as can most psychics (magic and psionics have a lot of overlap points). It's something that Wandless practitioners tend to find much easier, thanks to their more raw connection to magic. More precise or ranged detection requires experience and training, which Harry gets in the sequel.
• In the Discworld continuum, A.A. Pessimal has a young witch explaining how she senses magic; to her, the canonical description of "the taste of tin in the mouth" becomes "It's like tasting really sour lemon juice and something metallic, acidic.". Her younger sister, who has some magic and burns it off in creative Art, has discovered how to make octarine paint - the eighth primary colour, only visible to magic-users - and incorporates this into her Art, much to the discomfort of non-magic-users who know something is there but can't tell what it is.
• Leafy Trace in Hinterlands is able to detect spells that have recently been cast in an area. Necromancy is repulsive enough to make her nearly vomit.
• Past Sins: From "Everfree Discovery", Unicorns, or at least Twilight, has a sense for magical energy through her horn:
  Yet, there was more to it than that. When they started to cast the spell, Twilight could feel it in her horn. The air became saturated with magical energy, and, as the spell began to progress, the magic began to change, to feel familiar. It was a kind of magic she hadn’t felt since… since…
  Twilight’s pupils narrowed into fine points from the horror of the idea she had formulated. What if the spell cast was supposed to bring back Nightmare Moon? And what if it worked?!
• In Powers of Invisibility, Tikki and Plagg explains that the fact that Juleka was unaffected by the Glamour protecting Marinette and Adrien’s secret identities was because she is a candidate to take on the role of the Guardian and wielder of the Turtle Miraculous. She then sarcastically refers to this as her "turtle sense."
• Triptych Continuum: Each major pony race has a sense for the detection of magic called feel, the quality of which varies by the individual (although some ponies can improve with practice). However, in reality, this actually works out to be three separate senses, as a pony can only pick up on the workings of their own race. Twilight's feel for unicorn magic is fairly acute, while Pinkie hardly ever registers even the strongest earth pony traces. The Princesses are presumed to possess all three versions. She also has all three — but only one at a time, and she doesn't know how to interpret some of the information, leading to a degree of synesthesia.
• A Scanner's talent in The Awakening of a Magus allows one to sense magic both in items and people, and even identify it for more powerful ones. Draco has it on a level above any ever documented. Mike Storm also has a bit of it, despite being a Muggle in all other senses.

Literature

• Sorcery in The Belgariad and related works makes what is described as a "sound", which can be mistaken for mundane noise under some circumstances. The sound can be lessened by doing things slowly, and shapeshifting, because it's directed internally, is very quiet. The protagonists are often forced to avoid sorcery in enemy territory because of this noise effect. Interestingly, other forms of supernatural power, such as magic, wizardry, necromancy, and prophecy, do not make this signature noise.
• Beware of Chicken: Meiling has access to a rare bloodline power that lets her smell chi. This can detect cultivators even when they are hiding their power from normal methods of chi-detection, and the odors she smells reflect the nature of the cultivation (demonic cultivators smell of blood and oil, Jin smells of earth and the predominant natural scents of the season, Bi De smells like the moon, and so on).
• Daughter of the Sun:
  • Orsina can detect if magic is near, and she found Aelia this way due to Aelia's chaos magic.
  • Aelia can detect people who serve fellow chaos gods by how this marks them, and the magic which they get as a result.
• Magic in A Day of Fallen Night comes from either siden (geological activity in the earth) or sterren (the stars). Although the children of someone who imbibes either source (or both) don't have full magic abilities unless they also partake, they are granted a certain affinity for magical events. Glorian, a descendant of Galian and Kalyba, can sense the Dreadmount's eruption and can communicate with a mysterious figure in her dreams—as can her mother, who believes it to be Saint Galian. Dumai, whose mother drank the tear of a dragon, can speak with dragons telepathically. Wulfert Glenn, the son of a Priory mage, is immune to plague and harder to kill by cold or fire.
• In Katherine Kurtz's Deryni, mages work this way. They can generally tell who is Deryni and who isn't, because Deryni have mental/psionic barriers called "shields" that are detectable over short distances. Some highly skilled Deryni can disguise their shields, making them seem transparent. Ordinary humans lack these shields, so their surface thoughts are easily apparent to Deryni. Transfer Portals have a residual signature that Deryni can feel and recognize (described as a tingling sensation coming from the area of the floor/ground where the Portal is located).
• Magic in the Discworld falls under both types. Strong magic leaves strong residue, to the point that especially strong magic can leave magical fields behind that warp reality and last for centuries, which magic users can generally sense as a sort of greasy feeling in the air. It has been described as "the taste of tin in the mouth". All magic users have the ability to see The Colour of Magic (octarine, an eighth colour which is outside the normal 7-colour spectrum), a colour which appears whenever magic is being used.
• Wizards in The Dresden Files can use their True Sight to see exactly what is going on. The Sight shows everything that's happening, in excruciating and often maddening detail, and one of the things that can be Seen is the residue of magic that has been used recently. Magical practitioners can also detect each other when they touch, meaning a practitoner hiding that ability needs an excuse to avoid shaking hands.
• In The Elenium series, use of magic can be detected in much the same way, but the range of detection seems to be much less. It's also possible to tell which spell is being used by the feel of it. Notably, the Bhelliom leaves a mark with its passing that any god or similarly powerful being can't help but feel, and using its power draws the attention of all such beings. This necessitates the protagonists to keep it in a gold box most of the time, which nullifies the effect.
• Magic users in Fancy Apartments can sense magic. There's also second sight, which is basically a more accurate and specialized version.
• Goblins in the Castle: The goblins are said to have a form of this, as Granny Pinchbottom admits that she's too powerful — they'd sense her coming long before she got anywhere near their king.
• In Harry Potter and the Half-Blood Prince it is suggested that powerful wizards who actually know what they're doing are capable of the residual type; in the cave scene Dumbledore is shown to determine where the secret entrance is and the spells used on it without the use of any detection spells.
  • In The Film of the Book, they add to this with Harry being able to sense the residual dark magic indicating that an object is a horcrux, which is necessary as they trimmed out a long dialogue where Harry and Dumbledore discuss what and where the horcruxes are. It also works as foreshadowing that Harry himself is a horcrux.
• Incarnations of Immortality: In For Love of Evil, Parry is tracked through France by a sorcerer who can sense when he does magic.
• Randall Garrett's Lord Darcy series. A Witch-Smeller can detect the taint of black magic on its caster and its victims.
• Inkmistress: Asra can sense life and magic. She's also capable of hearing songs sung by the gods which mortals can't.
• Mage Life, The main character makes use of additional senses attributed to his capabilities with magic.
• Robert A. Heinlein's Magic, Inc.. Dr. Worthington is a witch smeller, who detects and analyzes the magic forces that trashed Archie's store.
• Played with in the Mistborn series: a Misting who can burn bronze (known as a "Seeker") can detect Allomancy, but a Misting burning copper (a "Smoker") can hide it.
  • It's later revealed that very powerful Mistborn, like Vin, can even detect Allomancy through Copperclouds. Except even that is later revealed to be the result of a bronze Misting or full Mistborn getting another bronze Misting's power added to theirs through Hemalurgy.
• Of Fire and Stars: The Mynarians get ahold of an artifact that can detect if someone has magic. Following multiple attacks with spells on high officials, they start testing people using it, which dismays Dennaleia, who has magic. Also, mages can detect others with practice if they have moderate strength in magic, along with magic which things possess generally.
• Pale: When the Carmine Beast is murdered, she howls out and is heard for miles around, with sensitives bleeding from the eyes and knowing her despair. Less immense supernatural events can manifest through more oblique imagery, and Augurs try to collect and study information to understand what will happen.
• Quarters: Bards can tell instantly just by looking at Vree that there's another kigh (spirit) inside her along with her own.
• Reign of the Seven Spellblades: In addition to normal sensitivity to magic use, volume 2 implies, then volume 10 confirms, that users of the eponymous spellblades can subconsciously recognize one another when in close enough proximity to use them, a sensation formally known as "Grand Arts Synchronicity". This sensation saves Oliver's life when he mounts an Assassination Attempt against Demitrio Aristides: Demitrio defeats Oliver's Fourth Spellblade with the Fifth, but Oliver realizes a split-second before contact that he was facing another spellblade and pulls back just in time to avoid a deathblow.
• The Scholomance: The protagonist's innate affinity for all kinds of destructive magic also lets her identify anyone who's started using The Dark Side, even minimally. Unfortunately, that selfsame affinity is so strong that many others get the feeling she is actively using Black Magic herself.
• Linden in The Second Chronicles of Thomas Covenant has the empathic ability to sense when things in the Land are healthy or diseased. Too bad that Every. Single. Thing. in the Land is corrupted and poisoned by the Sunbane.
• Spellster: King's Hounds can sense magic and they track spellsters using this.
• Terran psychics in the Expanded Universe of StarCraft can detect each other. Even some weak ones without otherwise useful powers can do so. Many are hired as "wranglers", who hunt down psychic children and forcibly recruit them for the Ghost Program.
• Star Wars Legends: Luke Skywalker has Activity Detection just fine, but in The Courtship of Princess Leia he is conspicuously unable to tell if random people are Force-Sensitive.
• Swan's Braid & Other Tales of Terizan: Terazin is able to sense magic, but not work it herself. It comes in handy during her thieving for escaping magical traps.
• In Tamora Pierce's Tortall Universe, characters with the Sight can observe use of the Gift. Alanna also has a stone which, when held, allows her to see magic in use.
• Channelers in The Wheel of Time series can always tell if someone of the same sex is channeling nearby, and how strongly, but need to see the flows of Power in order to determine the nature of the weave used. Both the ability to channel and the weaves themselves can be concealed, by methods long-lost but rediscovered partway through the story. Weaves also leave a residue that can be read by other channelers of the same sex (though the ability is uncommon), the most common use being to follow someone who Traveled away.
  • Among their array of unnerving powers, Myrddraal can sense when someone is channeling nearby. This ability is nowhere near as sophisticated as that of a real channeler; one of them describes it as an "itch."
  • Gholam, designed to be assassins of channelers, seem to be able to sense the force and direction of channeling.
  • Female channelers can sense the ability to channel in each other, even if neither is actually touching the True Source at the time, although they do have to be quite close. Once they're touching the True Source they literally light up like beacons - another female channeler will, when sufficiently experienced, be able to see a glow around a woman who's holding or using the Power. However, they are completely unable to sense when a man is channeling or holding the Power, at least until his spell takes effect and leaves a residue.
  • Men, on the other hand, can't identify another man who can channel unless he's holding the Power, and even their sense of that is much less precise than the sense women have of each other. This is probably related to the role of female channelers as the catalyst for linking strength - men cannot link without women involved, but women can link without men. However, men (or at least, Rand) can sense when a woman nearby is holding the Power, although to them it generally feels like nothing more than a vague sense of unease.

Live Action TV

• Immortals in Highlander can sense the presence of other Immortals. In most cases this is signified to the viewer by a specific sound effect known to fans as 'the Buzz'. However, it can take other forms: Immortal Kit O'Grady starts sneezing when he senses another Immortal, while the Buzz for Methos sounds like laughter. The Buzz is only discernible at short range — say, under fifty feet or so, and many aspects of it change with the demands of the plot. Several episodes indicate that Immortals can also sense "pre-immortals"^note these are people who will become Immortal if they die under the right circumstances, but haven't done so yet as well. The whole thing was developed more for the series than the original movie, where it’s much less defined.

Tabletop Games

• Blue Rose adepts, regardless of specialization, all have at least some talent at sensing arcane occurrences and energies. Non-adepts can either specifically train in the Second Sight, or get magic stones that glow in the presence of arcana.
• In Candela Obscura, supernatural beings often leave behind traces of their magical essence, known as "Bleed", in places they visit. Player Characters can detect this with a device known as a "Bleed detector".
• Dungeons & Dragons:
  • The spell detect magic lets magic-users see magical auras. Sufficiently long study (and a sufficiently high roll) allows the spellcaster to determine what school of magic the magic is from, and what the magic (or magical item) does.
  • Some monsters had the innate ability to detect magic (as the spell), such as several types of demons and devils, efreeti, imps, gynosphinxes and so on.
  • Several psionic monsters had the ability to detect the use of psionics nearby, such as the Brain Mole, Intellect Devourer and Thought Eater.
  • In 4th edition anyone with training in the arcana skill can detect magic at will.
• GURPS has the Detect advantage, which, depending on what it detects, can by all means detect something supernatural.
• In In Nomine characters with supernatural powers (mostly angels and demons, but some special humans as well) can detect "Symphonic Disturbances" caused by use of certain supernatural powers, and/or controlled Essence expenditure nearby.
• Characters in the New World of Darkness can purchase the Unseen Sense merit, which will let them detect one particular sort of supernatural activity. A character with Unseen Sense (Vampires) would be able to pick up when a vampire uses a supernatural ability nearby, but could not pick up on someone simply being a vampire. Mages get a form of Unseen Sense that picks up all supernatural activity and get the "residual detection" form of this trope from scrutinizing the resonance of something through various Mage Sight spells.
• Characters in Reign can learn the Eerie skill, tied to the Sense stat, to detect the use and presence of magic. Anyone has access to Eerie whether or not they can perform magic, and can roll just their Sense stat even if they're completely untrained in the skill. It's a natural sixth sense that everyone has, even if some neglect to pay attention to it.
• Shadowrun. Anyone with the ability to perceive astral space (including magicians) can "see" magic use, including spells. Awakened creatures with the Magic Sense ability can detect the presence of magic, including Awakened characters (e.g. magicians) and other Awakened creatures.
• Ars Magica: Some people have innate Magic Sensitivity that they can train as a skill. It lets them detect the presence of magical locations, creatures, items, and effects, but renders them Weak to Magic.

Video Games

• In Devil Survivor, the protagonists eventually become able to sense the proximity of wild demons after gaining experience in fighting them off.
• In Dragon Age, the Fade is a metaphysical realm existing alongside Thedas, that all races (barring Dwarves) enter when they dream. Since Mages derive their powers from their strong connection to the Fade, they are uniquely capable of sensing locations where the Veil separating the two worlds has become weak.
  • Every tainted being (Grey Wardens, darkspawns, ghouls) can sense the taint in others beings.
  • Templars can sense magic and the presence of demons.
• Persona-users in the Persona 2 duology can sense a "resonance" when they get close to other persona-users. The idea doesn't really come up in other Persona games except with Fuuka (in Persona 3) and Rise (in Persona 4), who both play Mission Control.
• In the StarCraft universe, some weaker psychics get jobs as "wranglers", using their powers to locate other psychics. Zerg also have this ability. The ability of other psychics to detect psionics depends on who is writing the novel.
• In Tales of Phantasia and Tales of Symphonia, people with elven blood can sense the flow of mana, allowing them to recognize when magic and magitechnology are being used, measure the world's background mana, and distinguish the mana signatures of elven-hybrids from those of pure-blooded humans.
• Death Stranding: the player character, Sam, has a condition known as DOOMS, and can vaguely sense when BT's are close, but he cannot see them. Those with higher levels of DOOMS can see BT's... or even control them.

Visual Novels

• Mages from Fate/stay night can sense the use of prana in various ways. Emiya Shirou is particularly sensitive, and detects magecraft as a scent.

Web Comics

• El Goonish Shive:
  • Raven can "taste" magic through his ears, and analyze the nature and power of the spell by the "flavor" of the magic, because he is half-Immortal. Diane shares this ability, since she's Raven's daughter.
  • Tedd Verres has the ability to see magic spells being cast, and tell details about the spell itself, an ability shared by all seers. Seers exist to slowly reeducate people on how magic works in case magic decides to change.
  • Luke has the ability to see who has magical abilities and how powerful they are, although not what that ability is.
• Unsounded:
  • Sette has the unique ability to smell magic, though not well enough to stop her from walking right into a gossamer snare trap.
  • Skilled spellwrights can feel fluctuations in the Background Magic Field of the Khert when there's unusual magical activity in the area. The Platinum caste have the strongest connection to the Khert and are the most sensitive — the disturbance from some dangerous Magitek leaves Quigley itching uncontrollably and slurring his words.
• Jack O'Malley from Widdershins can see people's auras and invisible (but not intangible) spirits that were improperly summoned. He hates it because crowds and wizards hurt to look at, and it's left him completely colorblind except to those auras and spirits.

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