[[quoteright:330:[[Film/{{Hellboy}} http://static.tvtropes.org/pmwiki/pub/images/hellboy_blood_magic_2716.jpg]]]]
[[caption-width-right:330:Yet who would have thought the old man to have had [[OverdrawnAtTheBloodBank so much blood in him?]]]]

-> ''"Blood is sound, sound is words, and words are power!"''
-->-- '''[[SpellBook Grimoire Weiss]]''', ''VideoGame/NieR''

Spilling of blood is a [[ThePowerOfBlood potent force]] in the working of magic. It may be a token sacrifice, but it may also be [[CastFromHitPoints the loss of life that fuels the spell]]. Expect mages who practice Blood Magic to be portrayed as [[BlackMagic evil]], or [[TheDarkArts at least dark grey]], with possible exceptions made for {{druid}}like nature cults that may be considered [[NatureIsNotNice amoral]].

Some blood may be indicated to be more powerful than others. Common types are human blood, the [[RoyalBlood blood of royalty]], the blood of a special line, the blood of an innocent, a child's blood, the caster's own blood,[[note]]as a self-sacrifice, this version is the only one even remotely likely to be practiced by good characters[[/note]] or [[VirginSacrifice virgin's blood]]. Sometimes only a single person's blood has power, and any other blood is powerless.

The other side of the coin is menstrual blood, which is used much less frequently but is associated with life magic when it is used. Except, of course, when it's the MenstrualMenace.

This trope is OlderThanFeudalism, with blood and sacrifice being powerful magic in some of the oldest tales. A very old Greek {{curse}} was for a witch to run three times around the house she wished to curse while menstruating. Especially potent if it was her first period. It is frequently the alternative to {{Necromancy}} as the "evil magic".

Often overlaps with BlackMagic, TheDarkArts and CastFromHitPoints. See also OurVampiresAreDifferent and BodyToJewel.

Frequently a part of any ritualistic BloodBath. When it's the blood itself doing the damage, you have BloodyMurder. When the magic is used to extend the user's lifespan, it's LifeDrinker. When it's used to create life, it's FertileBlood.

May even overlap with TomeOfEldritchLore, which is often written in man's blood on parchment made of human flesh. Is often a cause for a SuperhumanTransfusion.



[[folder:Anime & Manga]]
* In ''Manga/AnatoliaStory'', HotWitch Nakia brings a girl from our times, Yuri Suzuki, to the Hittite Empire since she want to use her blood for a spell that will allow her to kill her stepson Kail and place her own son Juda as heir. [[SpannerInTheWorks Too bad]] [[PluckyGirl Yuri]] was smarter and more willing to fight back than Nakia thought she'd be...
* In ''Manga/{{Berserk}}'', the Behelits that summon the Godhand are activated when they come into contact with blood. This usually, but not always, happens during their owners' DespairEventHorizon, which makes them that much more willing to [[KillTheOnesYouLove sacrifice the people they most hold dear]] to [[DealWithTheDevil be reborn as a demon]].
* In ''Manga/BlackCat'', Sheldon's Tao is manipulating blood.
* In ''Manga/{{Bleach}}'', [[spoiler: Giselle Gewelle [[PeoplePuppets controls the bodies]] of whoever gets splattered with her blood. When a member of the 11th Division wounds her and both he and his companions have Giselle's blood on their clothes, [[NightmareFuelStationAttendant she]] [[DissonantSerenity cheerfully]] [[PsychicAssistedSuicide forces them to]] commit {{seppuku}}.]]
** [[spoiler: And if she can get her blood in a Vandenreich/Quincy, they literally become a corpse under her control. [[ShockAndAwe Candice]] is aware of this and prevents Giselle from doing so when [[TheMedic she]] heals [[AnArmAndALeg her amputated arm.]] The same cannot be said for [[FateWorseThanDeath poor]] [[MadBomber Bambietta]].]]
* One of the Contractors in ''Manga/DarkerThanBlack'', Wei, is able to teleport away anything that is covered in his blood. This power is frequently used to create gaping holes in the torsos of his enemies. Naturally, the only way he can use this power is by [[NightmareFuel carrying a knife and cutting his own wrists to toss blood on opponents.]] In case you couldn't tell, [[BadPowersBadPeople he's a bad guy]].
* ''Manga/DeadmanWonderland'' has an interesting spin on Blood Magic: the eponymous Deadman are capable of using Branches of Sin, a magic that allows them to weaponize their blood, such as Ganta's bloody hand blasts, Seiji's arm blades, and Karako's blood armor.
* In ''Manga/FullmetalAlchemist'', Ed and Al used their own blood as an ingredient in their attempt to resurrect their mother. When that failed miserably, costing Ed a leg and Al his entire body, Ed used his blood to draw a seal on a nearby suit of armor, binding his lost brother's wayward soul to it. This is justified by noting that the iron in the hemoglobin bonded with the iron of the armor, and the destruction of the bloodseal would kill Al.
** Later, when [[spoiler:Martel is killed while inside Al]], some of her blood runs down and over Al's blood seal, making him black out. However, this also allows him to remember what happened to him [[DeathAmnesia beyond the Gate]].
** The transmutation circle to generate a Philosopher's Stone [[spoiler:needs to have five "crests of blood" made from killing. For the nationwide transmutation circle, five gigantic military engagements which could be more aptly called butcherings created the five crests needed to cover all of Amestris.]]
** In the [[Anime/FullmetalAlchemist 2003 anime adaptation]], Mustang ends up creating a transmutation circle out of his own blood [[spoiler:in order to defeat Pride.]]
*** In TheMovie based off of the 2003 anime, the circle to open the Gate only activates when it gets in touch with blood. Edward has a little blood on his glove the first time he opens it. The second time [[spoiler:Hohenheim gets mauled by Envy, while in Amestris Wrath dies.]]
* ''Manga/{{Hellsing}}'', where it is referred to as "the currency of the soul." What it means is that vampires like Alucard absorbs their meals' souls when they consume their blood. Seras discovers this truth when she consumes Pip's blood, collecting his soul, becoming a true vampire, and herself gaining some of the Power of Blood. Later, it's revealed that [[spoiler:the huge amount of souls he's consumed fuels his absurdly powerful HealingFactor -- and that he can release his victims as a macabre army of the undead]].
* ''Mermaid Saga'' is [[ShoutOut referenced]] in ''Manga/HellTeacherNube''. Here, flesh from the (still living) mermaid Hayame has a 100% success rate, and her blood can instantly heal ''any'' injury no matter how grave, without conferring immortality. It does have the side effect of making the recipient into a moron for a short while, seeing as it comes from [[TheDitz Hayame]], after all.
* In ''Manga/InuYasha'' the [[{{Miko}} priestess]] Hitomiko is able to launch invisible blades using her [[MagicWand shrine bells]] to cause blood letting wounds on her enemy which then paint a circle on the floor binding them magically. She can also cause the blood to [[PlayingWithFire combust]].
** ''Anime/InuYashaTheMovieFireOnTheMysticIsland'': The [[BigBadEnsemble Four War Gods]] create a [[CloningBlues clone]] of Kikyo using a sample of her blood.
* One of the ways the title character of ''Anime/IzettaTheLastWitch'' can channel her magic is through her blood. A few drops scattered on snow, for instance, can let her call forth [[AnIcePerson spears of ice]] capable of impaling speeding fighter planes.
* Some of the magic in ''Manga/MahouSenseiNegima'' works like this. At one point, Negi bites his thumb hard enough for blood to pour out, then creates magic circles for The Thousand Bolts (the ultimate lighting incantation) and pulverizes a mountain sized rock. Blood of powerful mages also seems to carry a certain amount of energy in it if Evangeline is to be believed. ''If.''
* In Creator/RumikoTakahashi's ''Manga/MermaidSaga'', mermaid flesh can, if you're ([[WhoWantsToLiveForever un]])lucky enough to survive eating it without becoming a [[TheCorruption Lost Soul]], turn you immortal. But in the "Mermaid Forest" story, all that Sawa has is a flask of mermaid blood to heal [[IncurableCoughOfDeath her sister's illness]]. It made Towa immortal, but deformed her arm like a Lost Soul's, and now she regularly replaces it with arms cut from the fresh corpses of young women.
* ''Manga/MyHeroAcademia'' has villains with blood-related powers -- HeroKiller Stain can paralyze people whose blood he ingests for a certain amount of time (depending on their blood type), while his LoonyFan Toga can shapeshift into people whose blood she ingests. Notably, there's a teacher at UA who has a "Blood Manipulation" quirk, but he has not yet been seen in action.
* Some of ''Manga/{{Naruto}}'''s [[SummoningRitual Summoning Rituals]] use this.
** By drinking someone's blood and then standing on a symbol also made of blood (which doesn't have to be theirs), Hidan can turn himself into a living voodoo-doll for his opponent.
* In ''LightNovel/{{Overlord}}'', [[OurVampiresAreDifferent Shalltear Bloodfallen]] gathers the blood of her victims into an orb that hovers above her. She can use the blood as a substitute to mana, or she can [[BloodBath bathe herself in it]] to [[TheBerserker drastically increase her strength at the cost of becoming uncontrollable]].
* The ''Manga/PrincessResurrection'' manga uses blood magic as a fairly major plot point. The anime changed it to [[TechnicolorFire fire/energy.]] The manga would also eventually use fire instead of blood, but MUCH later into story, close to the end.
* In ''Anime/PrincessTutu'', Fakir revives Mytho's CoolSword by cutting his hand, and pouring the blood from the wound into a fountain, and reciting a spell [[GratuitousGerman in German]] while dipping the blade into the bloody water. The various applications of Raven's Blood (like [[FaceHeelTurn turning Mytho evil]]) might apply here, as well. In fact, ''all'' of the "in-story" magic seems to involve blood or [[HeartTrauma hearts]] (Kraehe presumably gets her powers from the Raven's blood in her, Tutu gets hers from [[spoiler:the Prince's heartshard]], the Raven gains power by eating hearts). Also, [[MadArtist Drosselmeyer]] [[RewritingReality wrote a very powerful story]] in his own blood, and [[spoiler:Fakir]] was only able to effectively rewrite the story after he had spilled his own blood onto a page.
* In ''Anime/PuellaMagiMadokaMagicaTheMovieRebellion'', Sayaka Miki normally needs a body of water to [[spoiler:summon Oktavia von Seckendorff]], but she can use her own blood as a substitute in a pinch.
* In ''Manga/TongariBooshiNoAtorie'', a criminal witch uses blood to produce magic ink needed to draw magic.

[[folder:Card Games]]
* ''TabletopGame/MagicTheGathering'':
** A vampire planeswalker known as Sorin Markov is said to use sangromancy (blood magic), which enables him to drain the lifeforce of other beings, place curses on enemies, and possess the minds of others. It is also implied that he can leech mana from opponents. How exactly he uses blood is not stated. Sorin's grandfather Edgar Markov turned himself and Sorin into the first vampires on the plane of Innistrad using a combination of sangromancy and a DealWithTheDevil.
** Long before he showed up, the ogres of Kamigawa, a Japanese-themed world, used blood oaths to bind oni (demonic spirits in this setting) to their service. This was represented mechanically by ogres with abilities that "turned on" when you also controlled a demon, and demons with drawbacks that "turned off" if you controlled an ogre.
* TabletopGame/SentinelsOfTheMultiverse features the Court of Blood and it's various blood mage vampires. Blood magic involves the manipulation of peoples blood in order to fuel your power. Or you can ise your own blood which is more painful to you but you don't have to kill anyone.

[[folder:Comic Books]]

[[folder: DC ]]

* Not a major example, but in one ''Franchise/{{Batman}} Detective'' storyline, ComicBook/{{Zatanna}} had been shot in the throat and nearly drowned in a death trap courtesy of [[spoiler:the Joker]] ([[VillainBall don't ask]] why he didn't just shoot her in the head). She avoided bleeding to death by using her blood to write out a healing incantation, made extra-strong by its medium.
* Comicbook/JohnConstantine {{Expy}} [[ComicBook/DoomPatrol Willoughby Kipling]] points out that the easiest and most blood-efficient way to do this is with a papercut on the page of the spellbook you're using.
* This is how Atrocitus created the Central Power Battery for his [[Franchise/GreenLantern Red Lantern Corps]]. In addition, he is capable of scrying through arcane blood rites.
* ''ComicBook/RedHoodAndTheOutlaws'': Red Hood's All-Swords get extra power from his blood. Or, something like that. It hasn't been explained yet.
** Minor opponent December Graystone previously used the name "Blood Mage", and continues to use his blood to cast spells.
* In ''Comicbook/TheSandman: A Game of You'', menstrual blood is used to power a spell to send the characters into Barbie's dream and come back alive ([[spoiler:mostly]]). The spell is repeated with blood from a cut palm in ''Death: Time of Your Life''.
* The ''Comicbook/TeenTitans'' villain Brother Blood leads a cult who focuses magic through bloodletting (yes, he's a little different from [[LighterAndSofter the cartoon version]]). One of his best-known acts was resurrecting Raven to be his bride (it was basically the writers' way of bringing her back to coincide with the success of the [[WesternAnimation/TeenTitans cartoon]]).


[[folder: Marvel ]]

* Nico from ''ComicBook/{{Runaways}}'' can only summon her Staff of One when she is bleeding. Menstrual blood also works in this case. It also allows her to circumvent one of the restrictions the spell has ([[spoiler:reviving the dead]]) during ''ComicBook/AvengersArena'' after she sheds enough.


[[folder: Other ]]

* ComicBook/ConanTheBarbarian once battled a witch who used a particularly nasty curse triggered by blood. Only a single drop of spilled blood was necessary to cause her victims to age rapidly and die within seconds, leaving behind a withered corpse. The only protection against the curse were magic talismans owned by three brothers who were the witch's enemies.
* The Queen of Witches from ''ComicBook/{{Hellboy}}'' has a thing for blood:
--> ''"Now she calls herself a goddess of war, but her war has no object other than the spilling of blood. All blood. Nothing but blood. Blood. More Blood. Nothing. But. Blood. For in the end the moon will be as blood and the sea boil and the land burn."''
* Another parody happens in ''ComicBook/LenoreTheCuteLittleDeadGirl'', when she pricks her finger and spills a drop of blood on a doll. It turns out to be a vampire that was cursed to be an inanimate plaything, and her blood broke the curse. Unfortunately, he realizes he's still in a doll's body because the curse didn't break properly; she'd been embalmed.
* The ''ComicBook/{{Spawn}}'' universe features demons that need blood to power their various devices.
* ''ComicBook/{{Arawn}}'': After becoming a living god, Arawn can use his blood to bring people BackFromTheDead.
* Blood magic was forbidden in the backstory of ''The Blood Queen'' as a compromise by the high kings of man so they wouldn't have to exterminate the WitchSpecies. The main character herself and several other dark wizards still use it in secret, however.

[[folder:Fan Works]]
* Shinji in ''Fanfic/PointsOfFamiliarity'' bites off his finger and sacrifices it to ... ''something'' to create [Masks].
* Subverted in-universe in ''Literature/TheDresdenFiles'' fanfic ''Fanfic/FairVote''. The protagonist uses tea as a metaphysically symbolic substitute – and it works.
* ''FanFic/AGrowingAffection'' has both the powers of the Blood Drinker demons, and Naruto's Blood Clone Jutsu.
* ''FanFic/EscapeFromTheHokagesHat'' has Naruto with multiple seals placed on him (by various Konoha ninja) to limit his growth. They were all made with blood. His own. After many a beating. Judging from a bit of dialogue between Tsunade and Shizune when they find out, placing a blood seal on someone is implied to be excruciatingly painful. Naruto got them between the ages of 6 and 9.
* In ''Fanfic/PerfectionIsOverrated'', Toki's Child, Cronos, has the ability to spawn black dragon minions from its own blood. She sends them back in time in order to alter [[Anime/MaiHime Mai, Natsuki and Nao's]] pasts to prevent them from ever coming to Fuuka Academy, and after that plan is thwarted, sends them against the three when she faces them in combat.
* In ''FanFic/ANewOrder'' main character Anime/SailorMoon can only use her [[WaveMotionGun strongest spell]] when she is injured and bleeding. The more blood she's lost, the stronger it is.
* In the Harry Potter/Disgaea {{crossover}} ''Something Wicked This Way Comes'', Voldemort's locket horcrux is sealed behind a wall requiring blood, like in canon. Etna wonders why he didn't think to key it into his own blood, instead of making it so that anyone could enter if they cut themselves.
* Some creatures in ''Fanfic/FalloutEquestria'' are able to control and shape spilled blood. Littlepip gains that ability after reading the [[TomeOfEldritchLore Black Book]], [[BadPowersGoodPeople but she mostly uses it to create artificial clots for medical purposes]].
* Team 7 (Naruto, Sasuke, and Hinata) aka Team Lie (and later Neji) in ''FanFic/PeopleLie'' make a pact with Kyuubi, "Blood for power, power for blood." They deliberately sacrifice blood in exchange for power; Naruto enters his canon SuperMode whereas Hinata, Sasuke, and Neji all gain more powerful forms of their doujutsu.
* ''FanFic/ImGivingYouANightCall'': Alchemy can only be activated by applying blood to an array. The Elrics are unique in that they need very little blood to activate an array.
* In ''Fanfic/LokiAgentOfDoomgard'' a MadOracle's advice is to use Loki's own blood for tracking spells. As they're searching for alternate versions of themself this proves surprisingly effective.
* In the ''Webcomic/AxisPowersHetalia'' fanfic ''[[https://www.fanfiction.net/s/9412929/1/ Hetalia School for Vampire Hunters]]'', most magical rituals involve this to some degree, usually using your own blood to form intricate symbols, which then casts the desired magical result.
* Root uses some in the ''Fanfic/CatalystVerse'' after Control tortures her, killing all of Control's guards instantly and allowing her to escape.
* The ''Franchise/AssassinsCreed'' fanfic ''[[https://archiveofourown.org/works/5856241 Hellfire]]'' involves lots of this, as Malik is a blood mage.
* ''FanFic/{{crawlersout}}'': While Gellert Grindelwald studies magic in all its forms, there are certain magicks that not even he, a Dark Lord, is willing to practice -- BloodMagic is one of them. [[spoiler:It's a sign of desperation that he's willing to search for a master of this particular magic in order to find Fem!Harry. Even then, the guy refused to do anything for him as he felt that his expertise was unnecessary, suggesting that even he was wary of the magic he practiced]].
* In ''[[Fanfic/GuardiansWizardsAndKungFuFighters Guardians, Wizards and Kung-Fu Fighters]]'', we eventually see that [[BeethovenWasAnAlienSpy Elizabeth Bathory knew this kind of magic]], using it to, among other things, create weapons out of spilled blood, and protect herself from harm. Her spirit later teaches it to her fellow [[TheChosenOne Ben Shui]] reincarnations Rasputin and [[spoiler: Jade Chan]].
* In the ''Fanfic/EmpathTheLuckiestSmurf'' story "Where The Wind Carries You", which is an adaptation of [[WesternAnimation/TheSmurfs the cartoon show]] episode "Never Smurf Off Till Tomorrow", Tapper (who appears in the place of the adult Nat Smurf among the Smurfs who were taken by the hurricane and dumped inside a volcano from which they escape) claims the blood of Jesus Christ over himself and his fellow Smurfs to protect them from the sharks that come swimming around them, ready to devour them. Whether it is because of this or what Tapper says, the sharks eventually swim away, leaving the Smurfs unharmed.
* In ''Fanfic/EquestriaDivided'' [[NatureIsNotNice Fluttershy]] creates [[BiologicalMashup Everfree Wraiths]] by infecting ponies with her blood.

[[folder:Film -- Animated]]
* In ''Disney/ThePrincessAndTheFrog'', Dr Facilier turns Naveen into a frog as to have an easy means of extracting blood for a voodoo talisman that turns Naveen's BeleagueredAssistant Lawrence into a copy of the prince for his own ends.

[[folder:Film -- Live-Action]]
* In ''Film/{{Blade}}'', it's of little surprise that the ancient vampire artifact runs off of blood. Blade is strapped into a huge bloodletting device that causes his blood to fill up all the magical symbols below him, rather similar to the picture above.
* ''Film/TheGoldenVoyageOfSinbad.'' The wizard Prince Koura uses his own blood to create a homunculus.
* The page image comes from the first ''Film/{{Hellboy}}'' film; Ilsa and Kroenen kill their guide in order to resurrect [[BigBad Rasputin]].
* ''Film/TheNightFlier'': Dees visits the grave of one of the vampire's latest victims at night time, then cuts open his thumb to smear a bit of blood on the tombstone, allowing him to see where the Night Flier is going. This warlock routine sorta comes out of nowhere, as Dees was shown to be nothing but [[HorrorStruck a cynic of the supernatural]] before.
* In ''Film/PansLabyrinth'', the blood of a child is called for to open a gate, though the heroine refuses to take it. It still [[spoiler:technically works - it just happens to be the protagonist's blood. [[SecretTestOfCharacter And it would not have worked had the baby been used.]]]]
* ''Film/PiratesOfTheCaribbeanTheCurseOfTheBlackPearl'': Will's blood was needed to break the curse on Barbossa's crew. A blood sacrifice was required from every cursed pirate, but they had cast Will's father overboard before learning this, so Will's blood, as the closest living relative, was used as a suitable substitute. [[spoiler:Once Jack cursed himself, he also added his blood to lift the curse "at the opportune moment".]]
* In ''Film/PracticalMagic'', Sally and Gillian slice their palms and clasp hands to cure [[spoiler: Gillian's DemonicPossession.]] It also conveniently works as a [[spoiler: CurseEscapeClause]].
* The eponymous ''Film/{{Pulgasari}}'' starts off as a rice figurine made by a dying blacksmith that gets brought to life by the blacksmith's daughter, Ami, when she pricks her finger while sewing over it. Later in the film, she is able to revive him by cutting her arm and letting the blood drip into the pile of boulders trapping the {{Kaiju}}.
* In ''Film/SilentHill'' Christabella unintentionally invokes this trope when she stabs [[spoiler: Rose]] in the chest. The blood gushing from the wound destroys the church, allowing [[spoiler: Alessa]] to enter. Then all hell breaks loose.
* In ''Film/SinbadAndTheEyeOfTheTiger'', Zenobia uses her blood to animated the [[ALoadOfBull Minaton]].
* Ryuhei Kitamura's ''Film/{{Versus}}'' revolves around the "Blood of Resurrection", which the villain plans to use in the Forest of Resurrection to open some kind of a dark door and get "The Power". Zombies and reincarnated samurai are involved.

* ''Literature/ASongOfIceAndFire'':
** Blood magic is, in general, one of the more effective, powerful, and, according to many, dangerous magics known in the Song of Ice and Fire universe. Maegi have been known to predict accurate prophecy by consuming blood, and the burning of blood, body parts, and people (often in sacrifice to gods) is effective at accomplishing various magical tasks. There are also some basic rules; most prominently, only death can pay for life.
** Melisandre uses blood magic to [[spoiler: cause the death of Renly Baratheon]]. She also claims credit for the deaths of [[spoiler: Robb Stark, Joffrey Baratheon, and Balon Greyjoy]], but whether that's truth or fiction [[MaybeMagicMaybeMundane is very unclear at this stage]]. King's blood is her preferred type, and she uses a very broad definition of "king"; the blood of illegitimate children seems to work just as well as legitimate, the blood of the self-appointed King Beyond the Wall of the wildlings works as well as that of hereditary southern kings. Taking enough blood to [[HumanSacrifice kill the donor]] works better than extracting a non-lethal amount via leech.
** The maegi Mirri Maz Duur also uses blood magic to [[spoiler: [[AndIMustScream "heal]]" Drogo]] and the favor is returned by Daenerys when she [[spoiler: burns the maegi alive as part of the magic to awaken her dragons.]]
* In ''Literature/DragonBones'' by Patricia Briggs, the heroes find a heap of dead bodies that have visibly been used for blood magic, having runes cut into the skin. They give them a proper burial by burning the corpses and singing prayers.
* Creator/MercedesLackey loves this concept, and blood mages are frequently villains in her books. In the ''Literature/HeraldsOfValdemar'' books, at least, it's the sort powered by death, not the red stuff itself, and gathering it from anyone else is ''exclusively'' villainous. Good-aligned Mages and Priests occasionally use their ''own'' death energies to really make a HeroicSacrifice stick, though.
* In ''Literature/{{Stardust}}'', the witches use the hearts of living stars to prolong their youth as a form of blood magic.
* ''Literature/HarryPotter'':
** In ''Literature/HarryPotterAndThePhilosophersStone'', it's revealed that unicorn blood is so potent that drinking it can preserve the life of a somebody who is already dying, but the act of taking it - which involves killing something [[UnicornsAreSacred innocent and defenceless]] - is said to curse the killer with a "half-life".
** In ''Literature/HarryPotterAndTheGobletOfFire'', Voldemort uses [[spoiler: Harry's blood to reconstitute himself. This later turns out to have been a horrible idea, as it makes Voldemort himself an "anchor" to the mortal world for Harry.]]
** And in ''Literature/HarryPotterAndTheHalfBloodPrince'', one of the enchantments used to protect [[spoiler: a Horcrux]] can only be lifted with blood, if only because the caster wanted to make sure no one could enter without hurting themselves. Dumbledore is actually disappointed that Voldemort couldn't come up with something more inventive.
* In Creator/OrsonScottCard's ''Literature/HartsHope'', blood is the essential source of magic: the more precious the blood, the most potent the magic. Kill a rabbit, and you can stop a stew from boiling over. Kill a deer and be able to turn invisible. Then kill a man to get ''real'' power. In order to exact her vengeance, Queen Beauty therefore [[spoiler:kills her own newborn daughter, which allows her to acquire powers sufficient to subdue the gods]].
* ''Literature/KingOfTheWaterRoads'' - Magic "usually" takes a toll in blood and pain to cast, according to the only trained magic-user seen in the book.
* Creator/TerryPratchett's ''Literature/{{Discworld}}'' parodies this with the Rite of Ashk-Ente, which summons Death. It's implied that this is supposed to require a human sacrifice and dozens of magical foci, but magical refinements mean that it's now possible with only an octogram, three small bits of wood, and 4 cubic centimetres of mouse blood.
** This is further refined to just needing the octogram, ''two'' small bits of wood and a fresh egg.
*** Of course, most wizards go all-out with the magical foci anyway, because if you're not going to [[RuleOfCool fill up your ceremony with arcane gibberish and dribbly candles]], why did you even become a wizard in the first place?
** A straighter example is in ''Discworld/CarpeJugulum'', where [[spoiler:Granny Weatherwax uses this kind of blood magic against vampires by "infecting" them when they feed on her.]]
-->[[spoiler:'''Granny:''' I ain't been vampired, ''you'' been Weatherwaxed!]]
* In the ''Dragonlord'' series by Joanne Bertin, blood magic is frequently employed by the antagonists. In ''The Last Dragonlord'', the BigBad uses the lives of prostitutes to charge a magical artifact. He then sacrifices a member of a specific bloodline in order to attempt to enslave one of the titular dragonlords. In ''The Dragon and the Phoenix'', the blood of the high priest is used to bind a dragon, and the magic of the dragon is used in turn to imprison and harness the power of the phoenix.
* Creator/RickRiordan's ''Literature/TheHeroesOfOlympus'' series:
** Gaea plans to use Percy’s blood in some kind of sacrifice to bring down the gods.
** Per book three, it's any one male and one female demigod. She just really wants it to be Percy and Annabeth.
* Appears frequently ([[TropeOverdosed of course]]) in ''TabletopGame/{{Warhammer 40000}}'':
** In Creator/GrahamMcNeill's Literature/{{Ultramarines}} novel ''Warriors of Ultramar'', the Ultramarines contact another Chapter, the Mortifactors, and find their use of Blood Magic rather abhorrent.
** In Creator/DanAbnett's Literature/HorusHeresy novel ''Legion'', the [[ArtifactOfDoom Black Cube]] is activated by BloodMagic, which explains a ferocious attack on the Imperial forces: to shed ''lots and lots'' of blood.
** In Lee Lightner's ''Literature/SpaceWolf'' novel ''Sons of Fenris'', Cadmus uses Blood Magic, killing one of his officers who's guessed too much, to open a [[CoolGate portal]].
** In Creator/JamesSwallow's Literature/BloodAngels novels ([[OurVampiresAreDifferent double of course]]):
*** In ''Deus Encarmine'', a knife tastes Rafel's blood and sends it back, and a Word-Bearer, by tasting it, can judge his age.
*** In ''Red Fury'', the blood in the Bloodfiends gives them [[GeneticMemory memories of those whose blood they drank]], driving them crazy, SplitPersonality style -- and with a fierce desire to drink more blood, worsening the problem. Rafen, fighting one, can clearly [[WasOnceAMan recognize the source of its blood]], and [[DyingAsYourself dying]], it might have said, "Brother."
** A general example throughout the entire franchise is, oh, roughly half of everything the Chaos faction ever does. "BLOOD FOR THE BLOOD GOD" is, after all, one of their favored battle-cries.
* Creator/TamoraPierce makes use of this both in ''Literature/CircleOfMagic'' and the ''Literature/TortallUniverse''. However, it is made abundantly clear that the only approved use of blood magic is when the mage uses his or her ''own'' blood.
** A specific ''version'' of it can be found in "''The Immortals''" quartet. As proved with Cloud and Brokefang, any animal that ''ingests'' Daine's blood becomes ''very'' special and more like humans in thought.
* In the ''Literature/YoungWizards'' series, healing spells require blood (that isn't from the patient), usually the healer's own blood.
** In a more aggressive case, this is the reason why the Master Shark has been around since (practically) the dawn of time. If his blood is spilled, every shark in the world is drawn to his location and is sent into an extreme [[UnstoppableRage feeding frenzy]]. Nothing ''dares'' attack him.
* This is one type of magic used in the ''Literature/EvieScelan'' novels.
* Thaumaturgy in the ''Literature/DeepgateCodex'' books.
* In Creator/RobinJarvis' ''[[Literature/DeptfordMice The Oaken Throne]]'', the high priest of Hobb dips the Silver Acorn pendant in the blood of one Ysabelle's subjects three times during a sacrifice. Each time, he calls Hobb's name. This summons the evil rat god to the world. The bloodstains cannot be removed from the pendant, no matter how many times it is washed, until [[spoiler:Ysabelle unites it with the magic of the Starglass and becomes the Starwife]].
* In Holly Lisle's ''Literature/TheSecretTexts'' trilogy, each of the three schools of magic use blood/flesh sacrifices. The origin of these sacrifices reflects where the magic lies on the good to evil scale. Falcons use their own blood and are good. Wolves use others present at the time as a sacrifice and are bad. Dragons are able to use whole populations at a distance as their sacrifice and are [[BigBad Super Scary Evil]].
* In ''Franchise/{{Mistborn}}'', Hemalurgy is a magical art that involves killing a victim and transferring certain of their qualities to a recipient (the precise process involves both getting stuck with a metal spike, often a large one). Who the victim is normally doesn't matter, but if you want to transfer magical powers, you do need to find someone who has them to begin with. The precise composition of the spike and where it is stuck in the recipient's body determine precisely what qualities are transferred. Strictly speaking, the position of the spike on the victim's body is also significant when stealing powers - it's just that [[ImpaledWithExtremePrejudice through the heart]] works the best, and is generally lethal.
* In the ''Literature/WaxAndWayne'' series (sequel series to ''Mistborn''), all magic has been disseminated to the common populace--except Hemalurgy, which Harmony and his Faceless Immortals keep very secret. In ''Literature/ShadowsOfSelf'', Wax ends up with Spook's personal journal, which details Spook's careful study of Hemalurgy following Harmony's restructuring of the world.
* In Creator/DanAbnett's ''Literature/GauntsGhosts'' novel ''Blood Pact'', the witch makes extensive use of this. [[spoiler:On both the prisoner and Maggs -- she didn't realize she had gotten blood from both of them at first, but when she did, she tried to use Maggs to assassinate the prisoner.]]
* [[WolfMan The Canim ritualists]] of ''Literature/CodexAlera'' drain the blood from sentient beings (living or freshly dead) to fuel their sorcery. They demonstrate a wide range of abilities including summoning storms, shooting lightning bolts, conjuring flying demon-things to keep airborne enemies out of the upper atmosphere, unleashing poisonous gasses, and other similarly creepy and destructive things. The most decent ritualists, such as Marok, use only their ''own'' blood to fuel their magic; the ones who don't tend to lean towards being {{Evil Sorcerer}}s.
** This is [[TheFettered a severe limitation on their power]], since the quantity of blood is very important. The storm that covered the Canim's invasion is mentioned as having cost ''millions'' of their own lives to pull off. For a long time after the Canim invaded no magic was used, because they had an insufficient source of it. [[spoiler: When they started using it again it was revealed to be mostly fueled by Aleran slaves who had defected to the Canim and given permission to be drained after other Alerans killed them.]]
* The bloodline of Celtic god Cernunnos gives his descendants magical abilities they can use against him in ''[[Literature/TheWalkerPapers Urban Shaman]]'' by C.E. Murphy.
* In ''Literature/TheDresdenFiles'', the main character sometimes uses traces of people's blood to locate them, but it only works if it's very fresh. In ''Small Favor'', the Denarians use the blood of an unknown person to fuel their {{Hellfire}}-powered pentagram barrier.
** BlackMagic and rituals often use sacrifices of some kind, so even though using blood is not considered evil in itself, it tends to appear a lot in the bad guys' spells. Possibly the greatest display of blood magic yet seen is the [[OurVampiresAreDifferent Red Court's]] curse seen in ''Changes'', which required hundreds of human sacrifices to energise and then a final sacrifice to target its destructive power.
* Literature/KateDaniels draws blood wards, magic circles drawn in the caster's blood which draw their strength from the blood itself. They can also be broken by someone of similar blood, a loophole Kate exploits to her own advantage. [[spoiler: It is also found out that she can create armor out of her blood as well as weapons, but they disintegrate within seconds. A power she received from absorbing The Scarlet Star.]]
* In the ''Literature/NightWatch'' universe, the lower levels of the Twilight will quickly drain your energy; if you need to get out fast, spilling blood will do the trick.
* In Andy Hoare's Literature/WhiteScars novel ''Hunt for Voldorius'', the Alpha Legion uses it. The White Scars find bodies drained of blood.
* In Creator/RobertEHoward's ''Franchise/ConanTheBarbarian'' novel ''Literature/TheHourOfTheDragon'', one reason why Xaltotun let his allies die.
-->"Because blood aids great sorcery!"
** In "Literature/ThePhoenixOnTheSword", Thoth-Amon, immediately on regaining his RingOfPower, uses the blood of the man he murdered for it to summon a powerful abomination against his old tormentor Ascalante.
* Blood is noted as being particularly potent for drawing spell forms in the ''Literature/SwordOfTruth'' series, though it's trickier for ''lasting'' spell forms as blood will eventually dry out and thus weaken the spell. The People's Palace in D'Hara is a spellform[[note]]which, for reference, saps the magic of any non-Rahl wizard and bolsters the magic of any wizard of the Rahl bloodline[[/note]] that manages to get around this through the novel method of leaving the blood inside people. The blood therefore is always fresh, and people are always allowed to travel through the halls of the palace, keeping the spell ''very'' powerful.
* The British warlocks in ''Literature/BitterSeeds'' have to shed blood every time they [[SummonMagic summon]] the Eidolons, {{Eldritch Abomination}}s that find [[HumansThroughAlienEyes human life abhorrent]] and so are attracted to the spilling of blood. It takes more and more blood to summon them each time, until British Intelligence are forced to commit major acts of sabotage against their own citizens (such as blowing up passenger trains and air raid shelters) to keep the supernatural war effort going. Worse, the more blood is spilled, the more information the Eidolons have on the nature of humanity, a necessary precursor to exterminating us.
* In L. Jagi Lamplighter's ''[[Literature/ProsperosDaughter Prospero Regained]]'', blood can give power and life to those in {{Hell}}. Kinda awkward when hellish mosquitoes have figured out you are alive and so have blood.
* In Teresa Frohock's ''Literature/MiserereAnAutumnTale'' names written in blood are particularly potent magic.
* Subverted in ''Literature/CountAndCountess'', where a large part of the story hinges on the main characters' belief in the magical properties of blood. Turns out [[spoiler: there are no magical properties]].
* In ''Literature/TheOrphansTales'', starlight is really a blood of the sky and can be used to perform some kinds of magic, like ShapeShifting.
* In Creator/DevonMonk's ''Literature/DeadIron'', [=LeFel=] takes the child's blood for this.
* In Creator/DevonMonk's Literature/AllieBeckstrom novels:
** In ''Literature/MagicToTheBone'', used by Cody's captors.
** In ''Literature/MagicInTheBlood'', a villain steals some of Allie's, which seriously worries her.
* In Creator/StephenKing's ''On Writing'', he describes some symbolic associations of blood with life and death, sin and redemption (through sacrifice), and how they're used in ''{{Literature/Carrie}}'' as a parallel to the titular psychic's emerging powers and rampage.
* Malkar and Vey Coruscant in ''Literature/DoctrineOfLabyrinths'' are accomplished practitioners. They have been using this to keep themselves young and vital for who knows how many years. One of Vey's many epithets is "Queen Blood."
* In ''Literature/TalesOfKolmar'' demon-summoning mages and those aligned with them always have to give the demons some of their own blood. On the heroic side, a mage discovers that when she touches her own blood to a dragon's soulgem her demon-fighting powers are greatly enhanced, to the point of being able to dispel minor ones with a touch.
* In ''Literature/{{Nightrunner}}'' {{Necromancer}}'s combine Blood Magic with more traditional Necromancy, as well as SummonMagic, to do some truly scary things to the living and the dead alike.
* In Creator/AndreNorton's ''Literature/DreadCompanion'', Kilda has to bleed to get the grass that can act as a guide. She even has to pull it by the bleeding hand.
* In ''The Psalms of Isaak'', Blood Magick is the in-universe term for magical potions or powders that must be distilled from human blood (as opposed to the more common Earth Magick, which is created from naturally occurring compounds in the stone and soil). Blood Magick is usually extremely powerful, but can also be extremely hazardous to the user's health, and is considered a DangerousForbiddenTechnique in most of the Named Lands, though TheEmpire of Y'Zir uses it heavily (and has a religion based around it). Like most magic in the series, it's mostly used to enhance the user's physical abilities, but can be used to produce more spectacular effects through an unrevealed process- [[FantasticNuke the Seven Cacaphonic Deaths of Xhum Y'zir]], the most powerful and destructive spell ever created, is said to be a product of Blood Magick.
* In Creator/RuthFrancesLong's ''Literature/TheTreacheryOfBeautifulThings'', the Woodsman and the Goodwife use blood to tame the redcaps.
* ''Literature/ThePowerOfFive'': One of the things required to open Raven's Gate is Matt's blood, exactly the reason why he was adopted by Mrs. Deverill.
* The ''Literature/ObsidianAndBlood'' trilogy takes place in the Aztec Triple Alliance at its height. Almost all magic is blood magic, ranging from simple self-sacrifice by cutting the earlobes, to animal sacrifice, to outright human sacrifices.
* The Dark Ones’ tunnels in ''Literature/{{Murderess}}'' open when the person entering spills blood, either his own or someone else’s (or even an animal’s), on a stone slab next to the entrance.
* ''[[Literature/AMagesPower A Mage's Power]]'': Members of the Bladi Clan have a unique branch of magic that uses their blood as its catalyst. The blood of anyone else is useless for magical purposes.
* The blades that provide the name of ''Literature/TheSharingKnife'' series are carved from the bones of the local WitchSpecies (thighbones, by preference) and driven into living hearts to empower them for the purpose of slaying the 'Lakewalker's' enemies. [[DarkIsNotEvil The Lakewalkers are in fact the good guys]], the [[EldritchAbomination things]] they hunt will [[WalkingWasteland kill everything]] [[TheWorldIsAlwaysDoomed if even a single one is left unchecked]], any every ''other'' weapon just [[NighInvulnerability gets the latter's attention]].
* In the ''Literature/SchooledInMagic'' series, blood is used in many aspects of magic, but not commonly. It can be used to power ritual magic, to steal magic through necromantic rites, or to help target a spell on a specific individual.
* At the start of the ''Literature/ShatteredTwilight'' story ''The Farmer's Wife'', the eponymous wife uses a sacrifice of her own blood as part of a ritual to summon a demon.
* In ''Literature/TheBloodLadders Trilogy'' shedding blood is the easiest way to transfer magic. Elves use blood for a variety of purposes, the least of which is creating and feeding magically constructed creatures such as the genets, and the locks on their cages are also opened with blood. Among humans, the Church's priests put a drop of their blood, inherited from Saint Winifred the first human mage, into the communion chalice to grant their congregation some protection from demons.
* In ''Literature/ADarkerShadeOfMagic'', ''Antari'' magic is more powerful than other types of magic, but requires the caster to spill some of their own blood.
* In ''Literature/MaledictionTrilogy'' witches can use blood to perform more powerful, dark and dangerous spells. It is also the only kind of magic that works on troll - provided they use troll blood to power the spell.
* Early in ''Literature/TheRedTent'', it's mentioned that Rachel's first menstrual blood was collected and used to fertilize the crops, on the belief that [[MenstrualMenace menstrual blood]] [[VirginPower from a virgin]] makes food crops grow bigger and stronger. Interestingly, there ''is'' some truth to this, in that blood is rich in nitrogen, which does make it a good fertilizer, as any organic gardener who has ever used blood meal can tell you. ''However'' it does ''not'' have to be menstrual blood, and it does ''not'' have to be from a virgin (male or female). And it doesn't even have to be ''human'' blood. (The aforementioned blood meal, for example, is a byproduct of meat-processing.)
* In ''Literature/ShamanBlues'', blood is the carrier of magic, so sacrifices are made to obtain the power hidden within it.
* The Mosquito-kinden of ''Literature/ShadowsOfTheApt'' have a ''serious'' thing about blood, and huge quantities turn up in some prophecies.
* Also from ''Literature/SwordOfShadows'', it's possible for weaker sorcerers to enhance their powers by draining blood from a properly bound stronger sorcerer. [[EvilOverlord Penthero Iss]] demonstrates both the binding and the bloodletting in NightmareFuel detail.
* In the ''Literature/OldKingdom'' trilogy by Creator/GarthNix, the power of the Charter that gives the King, Abhorsen, and Clayr their unique abilities is found InTheBlood - as in, both genetically and literally. Charter Stones, which keep the magical Old Kingdom sustained, can be broken if a Charter Mage's blood is spilled on them (in death), and the [[CosmicKeystone Great Stones]] can only be broken by the blood of one of the Charter bloodlines (see above.) Finally, in ''Abhorsen,'' [[spoiler: Sam makes a sword to break apart the EldritchAbomination by combining, among other ingredients, blood from carriers of all [[strike: three]] four bloodlines.]]
* In the ''Literature/ChroniclesOfTheKencyrath'' with blood-binders- Kencyr who have the inherent magical ability of creating a telepathic link with anyone who's exposed to their blood, a link that is so powerful that can endure past death. [[OurVampiresAreDifferent Darkling Changers]] have a related ability of being able to take the form of anyone whose blood they've sampled. If a Changer tries to feed on a blood-binder, and the blood-binder's magic is stronger, then the Changer will be wracked by intense pain, the only known release form which is death.
* ''Literature/TheElenium'' plays with this. In this case blood isn't so much magical as it is innately capable of ''restraining'' magic. The living stone Bhelliom is supposedly controllable by two rings, each of which contains pieces of the original Bhelliom stained red with blood. Later, it's revealed that blood restrains Bhelliom for a very prosaic reason: [[spoiler:Bhelliom cannot stand the touch of iron, and human blood has iron in it]].
* In ''Literature/TheWheelOfTime'' series by Robert Jordan, we have the mindtrap; similar to a phylactery. Combined with the blood and saliva of a channeler(magic user), it captures the soul, or essence of said channeler. Should this fragile item be crushed in someone's hand, the holder will have complete control over the (now)mindless puppet.
* In ''Literature/NewArcana'', only people with mageblood can use arcane magic, and mageblood is a street drug. The Order's soul-binding ritual involves mingling the blood of the cohort members.
* In ''Literature/{{Pact}}'', blood is symbolic of the self, and can therefore be used as a source of power in an emergency-but only the mad or the desperate do this, because spilling blood is spilling the self, and a lot of Others ''like'' it when people are hollowed out shells-it gives them room to move in.
* In the ''Literature/MalazanBookOfTheFallen'', blood magic is the eldest form of magic. It goes back way before the Warren system was established by Elder God K'rul, the Maker of Paths -- which, ironically, was done using blood magic, and the Paths of Magic called the Warrens are technically his veins and the magic they provide is technically his blood. Additionally, K'rul himself and the other Elder Gods [[GodsNeedPrayerBadly need prayer badly]] in order to continue existing, and that prayer needs to be provided in the form of blood sacrifice.
* In ''Franchise/TheWitcher'', one of the huge plot points concerning [[spoiler: Ciri]] is that [[spoiler: she is a direct descendant of]] Lara Dorren, incredibly powerful elven mage and wielder of Aen Hen Ichaer (AKA The Old Blood), power allowing her to be an independent source of magical energy as well as creating interdimensional gateways. [[spoiler: Ciri]] was carefully crafted by strategic marriages, so that she gets both genes important to the Hen Ichaer - one inherited only by women, and one inherited only by men - and yes, it means incest. Taken even further by [[spoiler: Vilgefortz of Roggeveen, a prodigious mage who turns out to be the Big Bad.]] He concludes that, since blood is the carrier of power, he can just take the blood. So he intends to [[spoiler: impregnate Ciri, abort the pregnancy and inject himself with the placenta blood.]] The books don't state explicitly whether that would've worked. [[spoiler: Later explained that the reason why Aen Hen Ichaer comes from elves is that elves come from another dimension in the first place, and genetically engineered the Old Blood using magic to escape their dying world.]]
* ''Literature/ThePaperMagician'' has Excision, the magic channeled through human flesh. Blood is included, and seems to be the most frequently-used component. In the first book alone, we see blood-fueled spells to blast enemies backwards, teleport, divine someone's location, [[spoiler:instantly heal bullet wounds, control the movement of blood-tainted water]]...the list goes on.

[[folder:Live-Action TV]]
* In ''Series/{{Angel}}'', a demon from another dimension tries to contact [[spoiler:Jasmine]] with flesh magic. It's even nastier than it sounds.
** Angel is temporarily made stronger after he drinks the blood of Hamilton, the Senior Partners' liaison, during the GrandFinale.
** Spoofed in "Reprise" where two Wolfram & Hart employees are following a list of instructions for a goat sacrifice.
-->(reading from a booklet) "Make sure all troths are securely fastened and sacrifices tilted as shown in diagram F-12 to ensure full drainage into sacred offering bowl. Using a clean, diagonal motion, slit throat of sacrifice with the pre-blessed ceremonial dagger provided... I didn't see that in the box."
* ''Series/BuffyTheVampireSlayer'':
** Dawn's blood is used to open a portal. The emphasized plot point that [[spoiler:Buffy and Dawn have the same blood]] is the key to allowing Buffy to save the world.
** The trope is specifically lampshaded by Spike in the same episode.
-->'''Xander:''' Why blood?\\
'''Spike:''' Blood is life, lackbrain. Why do you think we eat it? It's what keeps you going, makes you warm, makes you hard, makes you other than dead. 'Course it's her blood.
** Angel uses his blood to open a portal, and is later needed to close it again.
** A stray drop of blood unwittingly opens a portal to let a fear demon possess a house.
** Blood of a Slayer, if drunk by a vampire, gives the latter great powers and NighInvulnerability for a while. In Season 3, this is used [[spoiler:to heal Angel.]]
** Willow uses deer blood in her magic to [[spoiler:resurrect]] Buffy. Specifically, she sits by a creek until a baby deer comes along, before she draws a knife and kills it for its blood.
** In season 9, Willow cuts Connor's chest with the scythe to use his blood to tear a hole in the fabric of reality.
*** She also uses Buffy's blood to [[spoiler:restore Dawn, who had been fading out of existence with Seed broken]].
** In Season 7, blood opens the Hellmouth. Acting on the orders of the First posing as Warren, [[spoiler:Andrew kills Jonathan]] to try this. Except it doesn't work: [[spoiler:Jonathan]] is anemic.
** In the Master's first attempt at an early parole, TheDragon Luke volunteers to become the Master's "Vessel", supplying him with power by feeding on human blood.
** It's Buffy's blood which ultimately allows the Master to break free. ("Prophecy Girl")
** In the Season Two premiere, the Master's acolytes attempt a ritual to bring him back to life. This involves slitting the necks of his adversaries (i.e. the Scoobies) and wetting his skeleton with their blood.
* The girls in ''Series/{{Charmed}}'' occasionally use blood in their magic. They used their own blood to summon [[spoiler: their ancestor Melinda Warren]], and some vanquishing potions only work when they include blood from the demon being vanquished (though sometimes other parts work, such as the [[spoiler: dragon's scale]], so it's not specifically blood).
* ''Series/DoctorWho'': In [[Recap/DoctorWho2005CSTheChristmasInvasion "The Christmas Invasion"]], the alien Sycorax use "blood control" to hypnotize a third of the population of Earth. Technically it's MagicFromTechnology, but one of the UNIT characters commented that it appeared like they were casting a spell. The Sycorax reverse-engineered their technology from invaders, and think of it as magic. ("Sycorax" comes from ''Theatre/TheTempest'', where it is given as the name of a dead witch, late mistress of the island and mother to Caliban.)
* In ''Series/FridayThe13thTheSeries'', almost every single one of the cursed items must be powered by a death to derive their benefits.
* ''Series/GameOfThrones'':
** Mirri Maz Duur knows it, calls it by name, and warns Dany that it has a terrible price.
** Melisandre uses it to (apparently) kill Stannis' enemies, though the circumstances surrounding their deaths are sometimes ambiguous.
** The witch Maggy, who predicts Cersei's future in "The Wars to Come", needs to taste her blood to do so.
** Shireen is sacrificed because of her king's blood in an attempt to end a blizzard.
* In ''Series/LegendOfTheSeeker'', Darken Rahl used Blood Magic at least once so far, using it as magic ink to write a message in a book, which then caused it to appear to a 'paired' book one of his military field commanders possessed (sort of a magic 'instant message' or 'telegram').
** In the [[Literature/SwordOfTruth novels]], Darken Rahl uses a kind blood magic in the form of consuming the brains and testicles ({{Squick}}!) of a young boy loyal to him to summon a creature of the underworld to ride and thus can travel anywhere very quickly. The journey books were introduced later in the series and did not require blood to operate.
** Also in the books, it's mentioned that blood is particularly potent for things like drawing spell forms, though usually other things like sorcerer's sand also work for spells. The biggest blood-fueled spell form in the series is [[spoiler:the People's Palace. The trick here is, the blood is still in the people going through the palace, which is how it's kept potent when just blood would have dried out and lost its effect long ago.]]
* In ''Series/{{Merlin}}'', blood magic shows up in one of the spells of Nimueh in season one.
** Later, Morgana uses the Cup of Life to create an immortal army by filling it with blood.
* ''Series/OnceUponATime'': "Blood Magic" as a concept shows up often, typically referring to magic barriers that can only be broken or accessed by the magic user who created it (or a blood relative). Blood being an ''ingredient'' is far less common, though it has been used, most notably in tracking spells and by Gothel in season seven, as she needs [[spoiler: the blood of the two people her daughter loves most (her father and the woman she loves)]] to enact her final spell.
* In the third season of ''Series/PennyDreadful'', Hecate [[spoiler:uses Ethan's blood in a spell that summons rattlesnakes to attack their pursuers]].
* In ''Series/{{Salem}}'', this appears to be the basis of the "grand rite" the witches plan, requiring the deaths of innocents condemned as witches. Blood and death are two of the hallmarks of witchcraft.
* In ''Series/StarTrekDeepSpaceNine'' when Kai Winn is attempting to read the Book of the Pah-wraiths (essentially the Bajoran ''Necronomicon'') it appears to her to be a blank book. Another priest catches her at it, is horribly shocked at finding his superior (essentially the Pope of his world) doing such a thing, and starts to run from the room to denounce her to the other priests. She picks up a letter opener and stabs him; his blood falls on the book and... what do you know, the writing becomes visible.
* In ''Series/{{Supernatural}}'', Azazel's lackeys used a squicky blood fueled ritual to communicate with him. Brady does the same to communicate with his master, [[spoiler: Pestilence]].
** In the fourth and fifth seasons, blood can be used to construct a sigil that will temporarily dispel an angel from the area.
** And in the fourth season finale, [[spoiler: it turns out the blood of the first demon, Lilith, must be spilled to complete a ritual to release Lucifer from Hell.]]
** And the Special Children got their powers from [[spoiler: Azazel bleeding into their mouths]].
** A season five episode had Sam, Dean and [[spoiler: Gabriel]] bound to a location via blood.
** The sixth season finale had [[spoiler: the gate to Purgatory open using a cocktail of virgin blood and blood from a Purgatory resident.]] They are really fond of this trope.
** In season nine [[spoiler: Abaddon]]'s followers do some kind of cutting ritual to revive her.
* On ''Series/TeenWolf'', this is a way for a {{Druid}} to attain increased physical and magical powers. Human sacrifices, selected because they possess a specific defining feature (e.g. virgins, warriors, healers, philosophers and guardians) are ritualistically murdered for this purpose.
* In the first episode of ''Series/{{Warehouse13}}'' the first artifact we see is a Mesoamerican statue (looks like a stone jack-o-lantern) that possesses a man when he accidentally cuts his finger on it.
* In ''Series/XenaWarriorPrincess'', the evil god Dahok requires the loss of "blood innocence" to bring forth his evil offspring, so his followers trick Gabrielle into committing murder. In this case, it's the loss of life that fuels Dahok's power, but Gabrielle's hands are also covered in blood.

[[folder:Myths & Religion]]
* Literature/TheBible:
** The Jews annually sacrificed sheep and doves as "pure" sacrifices to God in exchange for atonement for their sins. For christians, this is taken as a {{foreshadowing}} for Jesus's sacrifice during the crucifixion, using himself as the ultimate pure sacrifice to nullify everyone's sins permanently, which is why Christians don't sacrifice animals anymore.
** The Passover where the Angel of Death came to kill the firstborn children of Egypt, and the Jews painted their doors with lamb blood so the angel would know not to kill ''those'' firstborn children.
** As Richard Carrier memorably put it: "God needed blood to fix the universe, but only his own blood had enough magic so he [[UsefulNotes/{{Jesus}} gave himself a body]] and killed it".
* The mythical account of Shaka Zulu. In exchange for limitless power, Shaka is said to enter a pact with the witch doctor Issanoussi, who demands the death of Shaka's pregnant fiancée Noliwe -- and this turns out to be just the down-payment for "blood medicine":
-->"The medicine with which I inoculated you is the medicine of blood; so if you do not spill blood in abundance, it will turn against you, and it is you whom it will kill" (''Chaka the Zulu'' -- Thomas Mofolo)
* The Aztecs believed that the sun needed to be fed on the blood of sacrificial victims daily to prevent it from dying.
** The Mayans practiced ritual bloodletting (and sacrifice, too, but only when they were desperate). They also had a ritual ball-game that was not only ruthless, but ended in the winning team being sacrificed at the conclusion.
* In some parts of the West Indies, it used to be common to use animal blood at a boat's launching ceremony. Squeamish Americans and Europeans just use champagne, the wusses.
** A common story from the German and Dutch North Sea coast is that in the past people made live sacrifices when building dikes against floods. Burying a dog alive under the new dike would work, but a human child was considered preferable. The important part was, that a living thing had to be given to the spirits.
** Similar stories in Great Britain were told about human sacrifices being buried in the foundations of buildings. Actual skeletons have been found under Stonehenge, proving something like it did happen at least in some cases.
*** Unless, of course, the purpose of Stonehenge was, like the pyramids of Egypt, to be a burial site for people of importance. But where's the fun in that?
* In the Philippines, there is a mythical trickster spirit known as the Alan which is said to use reproductive waste, including menstrual blood, to create human babies, which it then lovingly raises as its own.

[[folder:Tabletop Games]]
* In ''TabletopGame/VampireTheMasquerade'', all vampires gain their abilities, obviously, from consumed blood. However, a few [[{{Splat}} clans]] take this one step further by developing a blood-based system of sorcery stronger than the hedge magic any human can learn but weaker than the Sphere Magick of Mages. The most well-known practitioners of blood magic are Clan Tremere, whose original members were Mages in life.
** ''TabletopGame/VampireTheRequiem'' carries this on with various forms of Blood Sorcery, the two most predominant being Cruac (a humanity-stifling, ritualistic art practiced by the Circle of the Crone) and Theban Sorcery (a series of "miracles" that [[EquivalentExchange require appropriate sacrifice]], practiced by the Lancea Sanctum). A third example is the bloodline power of the Gethsemani bloodline, which allows them to make mortals spontaneously suffer stigmata-like wounds; the blood from these wounds has magical effects on a vampire who drinks it.
** ''TabletopGame/HunterTheVigil'' features the Cainite Heresy, remnants of an ancient cult that weren't too happy after being dicked around with by a vampire claiming a direct connection to God. [[RiddleForTheAges Somehow]] they got their hands on vampiric blood magic, and created the Rites of Denial, special powers meant to deny vampires their innate advantages.
** ''TabletopGame/ChangelingTheLost'' has Tokens, magic items that activate with a simple burst of [[{{Mana}} Glamour]] or with a simple [[PowerLevels Wyrd]] check. Either of these can be foregone- and the items can be used by mortals- by paying the "Catch," a "dread cost." Examples? One, a minor thing that empowers your car, requires you to run your car on a pint of your own blood (one point of lethal damage); another one, a more potent one called a Pledge Stone, requires you to rip out your own tongue and burn it (one point of lethal damage and you don't have a tongue).
** And in ''TabletopGame/MageTheAwakening'', blood sacrifice (namely, draining a being, including a human, of its blood until it is dead) can be used to replenish {{Mana}}. The use of blood can also correspond to the powers of Mastigos or Thyrsus mages.
** Part of the reason the Garou of ''TabletopGame/WerewolfTheApocalypse'' slaughtered the Camazotz was the werebats' use of human blood in magic, which the Garou didn't understand wasn't a corrupt art. Combined with the Camazotz' demonic appearance and status as spies, the Garou sent the werebats into extinction. Which is heavily responsible for the totem Bat falling to corruption of the Wyrm.
** ''TabletopGame/GeistTheSinEaters'' has the Stygian Key, a source of power based around manipulating the raw essence of death. Few Sin-Eaters obtain it, as you need to drink from several rivers of the Underworld ''and'' make a deal with a [[EldritchAbomination Kerberos]] to learn its tricks. But even then, you can only use any of the Manifestations associated with the Key by performing a sacrifice first. There's also the Stigmata Key, which is much more common and allows the Sin-Eater to control blood and ghosts. Some of its Manifestations require a portion of blood in order to function, and it can sometimes be empowered by shedding blood when you don't need to.
* ''TabletopGame/{{Shadowrun}}''
** Supplement ''Aztlan''. Aztlan mages can use Blood Magic: spilling a human's blood to enhance spellcasting and summon Blood Spirits. Extremely evil, restricted to {{Non Player Character}}s. How restricted? If any player character starts learning Blood Magic from any source whatsoever, of their own free will, ''their character sheet is now that of an NPC.'' It's just that dark. Another reason for the NPC-turn is that Blood Magic is one of the most jealously guarded secrets in the world and Aztlan spares no expense in exterminating outsiders who learn about it with ''extreme'' prejudice. We're talking "nuke the block to get the guy who stole our secrets"-guarded.
** Expanded in the supplement "Street Magic". Adepts can benefit from blood magic, with at least one of the new metamagics revolving around ''cannibalism.''
** Come 5th edition source book ''Dark Terrors'', Blood Magic is now usable by player characters in a minor capacity. It's explained that the key differences with this new blood magic are a matter of scale & intent. Small scale blood magic using non-lethal amounts of blood either drawn in the normal course of combat or through willing donation is only half the equation; the other half is using it for selfless intent, to help protect & save others that you care about. Small scale blood magic, used in moderation, and used selflessly is the key.
** 5th edition blood magic also provides an alternative to augmentation in the form of blood crystals, which when applied to a severed limb or damaged organ can replicate the effects of cyberware & bioware without essence cost associated with those, thus allowing mages access to those benefits without sacrificing their power - unless the crystal is removed, in which case the essence comes with it.
* ''TabletopGame/{{Earthdawn}}''. Blood charms are used to seal Blood Oaths and gain magical benefits. They usually last AYearAndADay.
* ''TabletopGame/DungeonsAndDragons''
** In earlier editions, a magic user used his own blood as an ingredient in creating a homunculus, possibly inspired by the Sinbad example, though more likely inspired by real-world alchemists' practices, wherein it was believed human blood or human semen was needed to provide the homunculus a spark of live.
** The Cacodemon spell (which summoned a member of one the classes of named, but not unique, demons) had three methods to obtain a service from its target. Relatively moral mages could trap its spirit and exact a service for its freedom, or threaten to inflict torment on it until it agreed, but more evil mages could attempt to appease it with offerings, one of which was a bowl of mammal blood, preferably human.
** The Blood Mage prestige class allows a spellcaster use their own blood to improve their spells. There's a Wizard paragon path along much the same lines in Fourth Edition.
** In the book "Complete Arcane" for 3.5, the Prestige Class of "Blood Magus" is described as "formerly deceased spellcasters who, when returned to life, gain an understanding of their blood's importance..." They can create a homonculous as explained above, but they have many other abilities as well, a particularly frightening one being "Bloodwalk". With Bloodwalk, a Blood Magus can teleport by entering the body of a living creature the same size or bigger, either leaving peacefully or [[TeleFrag exploding out violently]].
** The Maho Tsukai from the ''Oriental Adventures'' can, like the 3rd Edition Blood Magus, use his own blood as a replacement for the material components for spells. He can also use someone else's blood, although that takes more time and more blood. Finally, he can use large amounts of blood (enough that it's represented by Constitution damage rather than regular hit point damage) to apply metamagic to his spells without using a higher-level spell slot.
** Many ''TabletopGame/ForgottenRealms'' spells are blood-related, like Bladethirst, Bloodstars, Blood Lightning, Beltyn's Burning Blood and elven Blood Dragon, and there are less specific mentions of elven blood magic in novels. Lots of other spells introduced in FR, while not inherently blood-themed, need as a spell component any blood (Revenance, Nulathoe's Ninemen), blood of specific creatures (e.g. red dragon for Daltim's Proof Against Fire, dwarf for Semipermanency) or the caster's blood (Bone Javelin, Elminster's Evasion, Fellblade, Immunity to Undeath, Lich's Touch, Mummy Touch, Phezult's Sleep of Ages, wizardly version of Negative Plane Protection). Components of magical inks, elixirs, etc appearing in Realmslore include blood of various creatures more often than not.
** ''TabletopGame/{{Ravenloft}}'' was ''created'' when Strahd von Zarovich murdered his younger brother Sergei, in a blood sacrifice intended to magically restore his youth.
* An obscure spell in ''TabletopGame/{{Pathfinder}}'' lets a caster use their own blood and [[CastFromHitPoints Strength]] in lieu of costly material components, which allows for such oddities as fueling powerful {{Summoning Ritual}}s and raising the dead with a generous helping of the red stuff rather than shelling out a fortune in gold and rare gems.
* [[OurElvesAreBetter Dark Elves]] in ''TabletopGame/{{Warhammer}}'' use blood magic. Their sorceresses can sacrifice wounds to get more magic dice, and they have large blood cauldros that imbues nearby units with the blessings of their god Khaine (also known as the bloody handed god).
* In ''TabletopGame/{{Warhammer}}'''s sister franchise ''TabletopGame/{{Warhammer 40000}}'', Chaos often asks you to starts shedding lots of blood -- whether it's yours or your enemy's depends on how Tzeentch is feeling that day -- for anything more complicated than boiling water, though the most common ritual in any given cult will be summoning daemons.
** And, lest we forget; '''''[[CatchPhrase BLOOD FOR THE BLOOD GOD! SKULLS FOR THE SKULL THRONE!]]''''' Khorne's followers really go nuts over this sort of stuff, although it's less about fueling magic than it is showing one' s devotion to Khorne and being rewarded with greater strength as a result.
** Appropriately, the Khorne Daemonkin faction has this built into their rules; Khorne units are incapable of using psychic powers or sorcery, so to buff them the Daemonkin were given the Bloodtithe rule. Any unit with Bloodtithe generates a counter for each unit it kills or if it dies, and counters can be accumulated and spent to provide a variety of effects, ranging from buffing your army to ''summoning a bloodthirster''. Because the mechanic doesn't care who dies, so long as someone does, this encourages players to bring tons of small, minimum sized units to get the maximum amount of bloodtithe counters for the amount of models they lose. Khorne truly does not care from whence the blood flows, only that it does.
* In ''TabletopGame/LegendOfTheFiveRings'', practitioners of ''maho'' fuel their spells by spilling blood, often their own. The explanation given is that ''kansen'', malevolent spirits, are attracted to the caster by this act and will then exert their influence over the world in accordance with the mahotsukai's wishes.
* In ''TabletopGame/{{Deadlands}}: Reloaded'' the Whateley Blood edge allows you to spill your own blood in order to gain "[[{{Mana}} power points]]".
** Under the original ruleset, [[BigScrewedUpFamily Whateleys]] got their own brand of BlackMagic that was actually accessible to {{Player Character}}s. It was fueled by blood drawn from under the characters' skin by otherworldly forces, and some of its examples [[BloodyMurder used the blood as a direct attack or defense]].
* ''TabletopGame/{{GURPS}}: Thaumatology'' codifies this: you have to spill enough blood to drain 20% of your HitPoints in order to get + 1 to casting. Unfortunately taking damage also makes it harder to cast a spell, so without the HighPainThreshold advantage there's not much point to it.
* In ''TabletopGame/{{Exalted}}'', all [[{{Necromancer}} Necromancy]] spells require a sacrifice of blood as part of the casting. In most cases, this is nothing more than a token sacrifice, and ''The Black Treatise'', the Necromancy {{sourcebook}}, notes that necromancers [[DoesThisRemindYouOfAnything tend to keep bandages handy.]] For the most powerful rituals, though, more gruesome sacrifices are required; Necromancy is very much BlackMagic in the world of ''Exalted''.
** There are also a few Sorcery spells that are not inherently evil and require the use of blood: Blood Lash only works when you are bleeding, and Benediction of Archgenesis, which requires the sorcerer to cut their feet and walk around the area they wish to [[FertileFeet bless with life]].
* ''TabletopGame/{{Scion}}'' features the Aztec Pantheon as one of its sample pantheons. As a result, Aztec Scions get access to the Itzli Purview, which allows the Scion to gain power through blood sacrifice. These powers range in potency from "sacrifice some of your blood to gain [[{{Mana}} Legend]]" to "rip out someone's heart and plug it into your own chest, where it catches fire and grants you new-found vigor."
** Likewise, Scions of the Aesir get access to Jotunblut, which allows them to use the blood of the giants to make mortal companions stronger. At the highest levels, it allows mortals to turn into giants themselves.
* ''Amber Diceless Role-Playing'', based on Creator/RogerZelazny's ''Literature/TheChroniclesOfAmber'' stories.
** A character with Advance Shape Shifting can use their own blood to create creatures which have some of their powers. These creatures are {{NPC}}s and not under the creator's control.
** A character with Shape Shifting and Conjuration can create items out of their own blood. A character with Advance Shape Shifting and Conjuration can create items out of ''other people's'' blood.
* ''TabletopGame/BleakWorld'' has a few vampires who can create blood golems, but the only people to get any real blood magic are the Waster witches who use it to restore their youth and the Demon Host who are granted special powers with blood.
* One issue of the ''[[TabletopGame/{{Rifts}} Rifter]]'' featured a school of blood magic. The mages were covered in cuts from using their own blood. They could take others' blood, but it had to be fresh enough, so there was a spell to render a vessel full of blood capable of preserving its contents. Other spells ranged from a simple, distracting [[Literature/TheTellTaleHeart heartbeat]] sound effect, through ''causing someones blood to eat their tissues from inside them'', to creating a blood golem.
* Rune magic is dangerous to use in ''TabletopGame/WeirdWarsWorldWarTwo'', causing backlashes which can cause the rune mage to die or be permanently brain-damaged. The ability of rune magic to turn people into thralls is useful here, as they can give the mage power (they don't track power points) and even absorb backlashes. This is going to kill the thralls, though due to the Final Solution they have plenty of people to enthrall and no rodents' posteriors to issue, as the magic is evil and only ever used by the Nazis. The process is usually referred to as blood magic and therefore it is more common to call the mages blood mages.
* In ''TabletopGame/{{Rifts}}'' and the Palladium universe, blood sacrifices are common for most kinds of magic because P.P.E. doubles at the time of death. But the actual representatives of this trope are Blood Shamans, who cast grisly spells from their own blood with a bit of Casting from HP.

[[folder:Video Games]]
* In ''VideoGame/PlanescapeTorment'', crystallized blood droplets are used for {{healing potion}}s.
* Taken to the extreme in ''VideoGame/FinalFantasyTactics'', in which human sacrifice is used on a titanic scale [[spoiler:by Lucavi, inciting a war with hundreds of thousands of casualties to spill enough blood to raise the BigBad Altima.]]
* Almost literally in ''VideoGame/FinalFantasyTacticsA2'', where the skill "Blood Price" lets you use HP to pay for magick instead of MP. The catch? The HP cost is double the normal MP cost, and you can't use your MP at all with this skill equipped. However, the simple convenience provided by it more than outweighs the drawbacks. Not to mention that you still get HP back if you use it for healing spells.
* In ''VideoGame/SoulSacrifice'', you are given an option to CastFromHitPoints for either short bursts on a wide area or continuous slashing. The only two who use this are [[CharacterCustomization the player]] and, most fittingly, [[FailureKnight Aegrus]].
* ''Franchise/DragonAge'':
** [[ExactlyWhatItSaysOnTheTin Blood Mages]]. Their magic allows them to CastFromHitPoints, drain the life energy of others to fuel their magic, control minds, boil others' blood in their veins, and sometimes even command demons. Despite this, they're [[DarkIsNotEvil not always evil]], but most are, and even the good ones tend to be treated as if they are, since the most common method of learning it is through a pact with a demon.
*** The player themselves can become a blood mage in ''Origins'' and ''2'', although ''Origins'' players have to unlock it[[note]]one time (once you've unlocked a specialization, it's permanent through all playthroughs)[[/note]] through--you guessed it--a deal with a demon during the "Arl of Redcliffe" quest. Oddly enough, nobody in either of your parties ever comments on your blood magic use, even when Merrill (an open blood mage) gets into arguments with the rest of the crew. Blood magic was dropped as a specialization in ''Inquisition'' and [[PreviousPlayerCharacterCameo Hawke]], who could ''be'' a blood mage themselves, is now very anti-blood magic ([[ItsPersonal although given what's happened, maybe that's not that surprising]]).
** The state religion of the Chantry demands that all persons with magical abilities have to permanently join the Circle of Magi and be confined to their towers where they are constantly monitored by templars who are to slay them at the first sign that demons have possessed their bodies. Every mage who tries to escape from the Circle of Magi or refuses to join is treated as being potentially possessed and killed. Since blood magic is not officially sanctioned by the Chantry, blood mages share the same fate as all other apostates.
** Ironically, the Chantry uses phylacteries, enchanted containers filled with the blood of Circle Mages, to hunt down any who try to escape. Destroying their phylactery is the only way a mage can ensure their freedom.
** The Joining - Grey Wardens gain their powers by drinking darkspawn blood mixed with lyrium. [[spoiler:The cost to this is the Darkspawn Taint eventually ''will'' overtake every Grey Warden, turning them into a Darkspawn themselves. They avoid this happening by [[TheLastDance suicidally venturing into the Deep Roads and trying to kill as many Darkspawn there as they can when they feel the taint has gotten too strong.]]]]
*** In the "Soldier's Peak" DLC, [[spoiler:the mage responsible for it being haunted by demons and undead has been experimenting to unlock the power of the Wardens' Tainted blood, including a ''lot'' of blood magic and human sacrifice. This gives Wardens who drink his concoction additional powers, whether it's bleeding on their swords for extra damage or spraying blood like a fire hose.]]
*** Conversely in ''VideoGame/DragonAgeOriginsAwakening'', it's eventually revealed that the sentient darkspawn that have been showing up originated from [[spoiler: a RogueDrone called the Architect who found out that he could use a mixture containing Grey Warden blood to turn other darkspawn into {{Rogue Drone}}s as well]].
** Another example of this are Reavers, warriors who ritually drink Dragon's blood and among other things, gain the ability to drain the lifeforce of others to replenish their own. Oddly enough, despite skirting very close into the same territory, becoming a Reaver is ''not'' frowned upon by the Chantry.
** In ''VideoGame/DragonAgeII'', the ''Legacy DLC'' reveals that [[spoiler: twenty years previously, Malcolm Hawke was forced by the Grey Wardens into using blood magic to reinforce the seals of an Ancient Grey Warden Prison. An unintended side-effect of this was that only those of Malcolm's bloodline are able to break through the prison's defenses and free [[BigBad Corypheus]], causing Hawke and their sibling to be targeted by the Carta]].
** ''Videogame/DragonAgeInquisition'' reveals that Red Lyrium is [[spoiler:lyrium Tainted by the Blight, which would only be possible if lyrium was alive. In other words, using lyrium to power magic is simply another form of blood magic.]] The [=DLC=] mission ''The Descent'' confirms this: [[spoiler: lyrium is actually the "blood" of enormous subterranean creatures called Titans.]]
* Another Creator/BioWare example is in ''VideoGame/JadeEmpire''. The defenses of Dierge were broken when the sacred fountains were polluted with human blood. [[spoiler: Useful in the nastiest way possible if you take the Closed Fist option]].
* In the ''VideoGame/{{Dominions}}'' series, spells from most schools of magic are cast using "gems" which are basically elemental forces (fire, water, etc...) concentrated into portable form, and the casting prices of spells are listed in these gems. Instead of gems, however, one school of magic lists spell prices in blood. These prices are listed in increments of one ''blood slave'', each of which must be drained completely empty, with high-level spell costs running into the hundreds. Blood magic is conspicuous in battle, where mages or priests are surrounded by a white-robed flock they systematically stab, especially if the mages start losing and set the slaves to charge into the spears of the enemies while they themselves flee. ''Dominions'' is not a happy series.
* In ''VideoGame/GodOfWarII'', at the Temple of the Fates, Kratos is required to capture a translator to read the incantation needed to open his path. Said incantation ends with the reader offering his blood as a sacrifice. Cue OhCrap just before Kratos bashes the guy's head in against the altar, his blood draining into a pattern etched onto the floor.
* ''Franchise/DevilMayCry''.
** When you kill monsters you collect their blood (which conveniently crystallized into red orbs in contact with air) to upgrade your magic powers. Justified in that there is a bounty system in placed by some nebulous god of good.
** In ''VideoGame/DevilMayCry3DantesAwakening'', [[spoiler: Arkham used the blood of Dante, Vergil, and Lady to open up the portal to the demon world. He needs this because the portal was sealed by Sparda (Dante and Vergil's father) using his own blood and the blood of a mortal priestess, Lady's ancestor]].
* ''VideoGame/CliveBarkersJericho'' has Wilhelmina "Billie" Church, a powerful blood mage. Her blood magic and abilities play a very important part in the game's story, and her spells can bind enemies and set them on fire.
** The Sumerian Demons Inanna and Ninlil also rely on blood magic (referred to as sanguimancy ingame). While Inanna uses the blood of Innocent people bound to torture wheels, Ninlil has herself locked within an Iron Maiden to spill as much of her own blood as possible.
* ''Franchise/WarCraft''
** In ''VideoGame/WarCraftII'' Death Knights, after being researched at the [[NamesToRunAwayFromReallyFast Temple of the Damned]] gain the spell Unholy Armor, which adds a [[NighInvulnerable nearly impenetrable]] [[ExactlyWhatItSaysOnTheTin suit of armor]] [[CastFromHitPoints at the cost of half of the target's HP]].
** In ''VideoGame/WorldOfWarcraft'', according to the background warlock's life tap ability (convert health to mana) works exactly like this (they sacrifice their own blood to gain mana), using it to summon most of their demonic pets, empowering their weapons or, curiously enough, a number of beneficial effects like summoning party members or Healthstones which can be consumed like a potion.
** ''VideoGame/WarCraftIII'' introduced Blood Mages, but despite the name they ''don't'' practice any of this; most of their spells are fire-based. Lampshaded by one you meet in the Blasted Lands, who says Blood Mages "eat normal food like normal people."
** Another example from WoW: The Mogu, resident {{Lawful Evil}} villains of Pandaria, utlize a mysterious red quantity called Anima to animate their Blood Golems, but it did not seem to be normal blood. It's not until late in the Isle of Thunder storyline that you find out what it is: the blood of [[{{PhysicalGod}} Ra-den]], the divine guardian of their species whose blood and secrets they stole and used to build their empire.
* In ''VideoGame/GuildWars'' a Necromancer's blood magic skills often have you sacrificing health to achieve an effect. The same class also uses Death magic, which exploits your dead opponent's corpses (and therefore blood) for similar effect, and their innate Soul Reaping ability, which heals you upon an enemy's death.
** Blood magic also has you drain health.
* This is one of the ways a Servant is summoned in ''VisualNovel/FateStayNight''. You take some chickens, put them to sleep, kill them, draw out their blood and make a magic circle. Then, you can either use a catalyst for a specific hero or just the general term of inducing madness in order to get a Berserker. Rider and Caster in ''Literature/FateZero'' were also summoned in this manner, and it's more noted upon there as well.
* In ''VideoGame/TheElderScrollsVSkyrim'' [[spoiler:The only way to open the old Blades headquarters in Skyrim is with the blood of a dragonborn.]]
** In the ''Dawnguard'' DLC, the lock sealing away Serana requires blood and a small puzzle to open it.
* The Dark Knight class that appears in various ''Franchise/FinalFantasy'' games has the ability to sacrifice health to either empower or fuel their attacks.
* [[AllThereInTheManual According to the manual]], the monsters in ''VideoGame/ZeldaIITheAdventureOfLink'' want to kill Link so they can use his blood to revive Ganon. They apparently succeed if you get a Game Over...
* Taken to the extreme again by Vladimir the Crimson Reaper, a [[{{Whatevermancy}} "hemomancer"]] in ''VideoGame/LeagueOfLegends''. Not only are all his abilities blood-related (including draining the blood out of his opponents and into him and briefly turning into a near-invulnerable pool of blood) but he fights with an orb of blood which hovers in his hands that he shoots at his opponents. His skins also seem to fancy him as the closest equivalent the game has to a [[OurVampiresAreDifferent vampire]].
* Grimoire Weiss of ''VideoGame/NieR'' absorbs the blood of fallen enemies to create magical constructs for his partner to attack with.
* Shao Kahn created Skarlet out of blood collected from various battlefields in ''VideoGame/MortalKombat9''.
* According to [[CuteWitch Marisa]], Remilia Scarlet from ''VideoGame/{{Touhou}}'' utilises this for a few spellcards. [[RunningGag Blood is amazing!]]
* ''VideoGame/TheSecretWorld'' features this as one of the three magical disciplines players can take on, and generally revolves around healing and damage (with life drain). Also, while with all skill sets you have to use weaker skills to build up "resource" charges which are spent on more powerful skills, you can still cast powerful blood magic skills without sufficient charges - you just sacrifice health instead.
* During the second ''VisualNovel/HatofulBoyfriend'', a MadScientist starts [[spoiler: drawing the blood of Anghel Higure, who has bizarre hallucinogenic powers tied to his fantasies, and using it so he can power a giant lazer with kidnapped otaku.]]
* During the second major part of Act V of ''[[VideoGame/DiabloIII Diablo III: Reaper of Souls]]'', which has you going through the Blood Marsh near Westmarch, you learn that [[spoiler:Adria]] has started using blood magic, creating blood golems and maddening the boggits, bogans and other monsters of the marsh to try to slow you down.
** Act III of vanilla ''Diablo III'' has [[spoiler:Adria]] borrow soldiers killed during the battle of Bastion's Keep to etch a ritual circle with their blood -- [[spoiler:one which strongly resembles the circles used by the Coven]]. [[spoiler:The circle she uses is to stabilize the Black Soulstone briefly, a window she uses to slam it into her daughter Leah, infusing her with all seven Evils with Diablo in charge.]]
* The melee skill tree in ''VideoGame/AvencastRiseOfTheMage'' is called Blood Magic, but it's more likely to reference blood spatter from melee-range physical attacks than dark mysticism.
* ''Videogame/EndlessLegend'''s Ardent Mages discovered that intense suffering allowed them to control [[ImportedAlienPhlebotinum Dust]] to [[MagicFromTechnology perform their magic]]. Ardent Mages practice ritual scarification, and their cities have floating jail-cells with trapped citizens to generate magic. One of their unique buildings, the Sacrificial Amplifier, [[LivingBattery has hundreds of living Mages strapped to a massive pillar which is burning hot]]; the description then notes that the magic generated is well worth it despite the cost of screams and stench of cooked flesh and shit.
* An inadvertent version in ''VideoGame/BrutalLegend''. When Eddie is badly injured due to the carelessness of the idiot band he works for, his blood drips onto his belt buckle and summons Ormagoden, kicking off the events of the game.
* In ''VideoGame/VanguardBandits'', the [[EvilWeapon monstrous Zulwarn]] [[AMechByAnyOtherName ATAC]] needs Blood in order to run.
* In ''VideoGame/{{Okamiden}}'', the BigBad Akuro must [[BloodBath bathe]] his [[DemonicPossession vessel]] in blood to become perfect. [[spoiler:Specifically, Orochi's blood.]] Or, maybe he has to bathe himself. The game can't agree with itself on this point.
* ''VideoGame/{{Messiah}}'': Satan feeds on human blood, which is what he needs to "physically exist in the Earthly realm"; he also seemingly derives his power from it. [[spoiler:Scientists' logs in the final level suggest that he managed to break free from his imprisonment in the research facility when they accidentally gave him too much blood to drink.]]
* The Healing Church's special blood in ''VideoGame/{{Bloodborne}}'' can cure any ailment and has cemented the church's power over the city of Yharnam. [[spoiler: Too bad it belongs to/''is'' an EldritchAbomination and gradually transforms people into horrific beasts.]]
* Do mods count? Minecraft has Blood Magic, Blood Arsenal, Blood Baubles and Sanguimancy, which all use blood - either drained from the player or from enemy mobs - to some degree. Its liquid form is called [[CallARabbitASmeerp Life Essence,]] but it's bright, blood red in color so it's rather obvious what it is.
* VideoGame/Disgaea5AllianceOfVengeance has Majorita, one of Void Dark's generals. Though called a Necromancer, it turns out her [[LimitBreak Overload Skill]] ''Broken Faith Magia'' is actually this, letting her control flesh via injecting a tiny bit of her own blood into a target. Powerful as this skill is, letting her revive downed troops to turn them into more useful zombies, [[spoiler: it turns out that targets with strong enough wills can resist the control, even to the point of disobeying her commands, and it can be dispelled with angelic magic (Thanks, Christo!). Later on, it turns out Void Dark only kept Majorita around due to this skill, and eventually uses his own Overload, [[PowerParasite Brigante Eclipse]] to take it from her and then immediately use it against her.]]

[[folder:Web Comics]]
* In ''Webcomic/SupernormalStep'', Jules and Van practice blood magic. However, Jules made Van swear not to use blood magic without his guidance. [[spoiler: Van later uses blood magic to contain a magic riot almost single-handed.]]
* ''{{Webcomic/Biscuit}}'' begins with a character opening an envelope sealed by blood magic.
* In ''Webcomic/{{Drowtales}}'', blood sorcery is a branch of mana manipulation.
** Syphile, Ariel's abusive caretaker, has an affinity for blood magic and uses it against Ariel at few times since she's especially vulnerable to it due to her own mana affinity.
** Chrys'tel is able to use her blood [[http://www.drowtales.com/mainarchive.php?sid=299 as a projectile]] and also [[http://www.drowtales.com/mainarchive.php?sid=8041 essentially make grenades]] using vials of it.
** Later on we get a dark take on the idea when a human king begins a campaign of kidnapping and brutally killing elves so he can [[BloodBath bathe in their blood]], hoping to gain immortality.
** Yuh'le, one of Snadhya'rune's proteges, has a particular potent combination of [[TheEmpath empathy]] and this that allows her to [[YourHeadAsplode explode]] people from a distance and make [[http://www.drowtales.com/mainarchive.php?sid=10233 bleed]] from every orifice.
* ''Webcomic/SluggyFreelance'':
** [[spoiler: The blood of the innocent awakes a powerful magic spirit in Torg's sword]].
** Only Gwynn can use [[TomeOfEldritchLore the Book of E-Ville]] to cast spells because her name has appeared on the inside cover written in blood. Right above instructions to, if lost, drop in any mailbox to return it to the rightful owner.
* In ''Webcomic/LookingForGroup'', when [[http://www.lfgcomic.com/page/44 Cale's swords]] are exposed to blood, they reveal a map to Kethenecia.
* Timmy from ''Webcomic/ParallelDementia'' can use blood magic.
* In ''Webcomic/FamiliarGround'', how they know that Toad's wizard is evil.
* In ''Webcomic/{{Tamuran}}'', [[http://www.tamurancomic.com/?p=161 the princes' blood is needed for a working.]]
* The Erlkönig in ''Webcomic/{{Roommates}}'' used his own blood to seal his son's magic and memories (symbolically his left eye). What power the guy has that a the blood of a blood related [[TheFairFolk fae]] [[RoyalBlood noble]] was needed is anyone's guess (maybe the Erlkönig is just a [[LargeHam show off]]).
* In ''Webcomic/PennyArcade'''s ''TabletopGame/EyrewoodAdventures'' comics, a person in dire need can summon the Thornwatch by tying briars in a particular way around a birch tree. No, you can't wear gloves: [[http://www.penny-arcade.com/comic/2013/09/16 "With bow and blood, the spell is done."]]
* In ''Webcomic/HeartCore'', there are a few characters who has this ability. [[BigBad Royce]] has shown to have the ability to controll spilled blood (his own and others) in order to use them as [[CombatTentacles strong tentacles]] that can grasp and crush bones of weaker creatures. Then there are the [[FierySalamander Salamander]] Demons, [[MadBomber Carval]] and [[PlayingWithFire Volaster]] [[LikeFatherLikeSon Jarvoc]] being some of them, who can use their black, flamable blood in order to creature very powerful fire-bombs in an isntant. That is, when they don't opt to turning themsleves into [[TakingYouWithMe living nukes]]
* Qarr in ''Webcomic/TheOrderOfTheStick'' mentions using virgin's blood as a spell reagent.
* Treneth in Webcomic/{{Visseria}} is shown preparing his magic-payloaded arrows by writing scrolls in his blood and tucking them inside.
* In ''Webcomic/TowerOfGod'', King Zahard transfers power to Zahard's princesses, his adopted daughters, by his blood.
* ''Webcomic/StandStillStaySilent'': When Reynir gives out his attempts at protection runes in Chapter 11, Sigrun suggests that they may work better if drawn in blood. Reynir is grossed out by the idea. It may also not be a good idea to try in his case: he is ''not'' TheImmune to ThePlague, there was a small scare when he barely avoided getting scratched by a PlagueZombie and he has to wear a breathing mask outside half the time as a precaution for the fact that ThePlague is partially airborne.

[[folder:Web Original]]
* In ''Roleplay/TheGamersAlliance'', blood magic is one of the magic schools which has a stigma on it when it was abused in the past. Because of this, very few mages are skilled in it, some notable exceptions being the [[TheMagocracy Alentian]] councillor Harrad U'niviel and the wandering sage Dieter von Waldheim.
* Fey has used this in the ''Literature/WhateleyUniverse'' against a dark mage who was trying to enslave her.
* Eva in ''Literature/VoidDomain'' is a blood mage. She usually uses it as a combative magic, but at least one example of using it in a ritual is shown.
* In the Breeniverse series ''WebVideo/{{lonelygirl15}}'' and ''WebVideo/KateModern'', infusions of Trait Positive blood can extend the human lifespan considerably. In ''WebVideo/LG15TheResistance'', [[spoiler:Maggie]]'s blood grants total immortality.
* ''Wiki/SCPFoundation'', [[http://www.scp-wiki.net/scp-2791 SCP-2791 ("Fauste Bank plc").]] The SCP-2791 creatures use blood magic contracts as part of their procedures to set up their convoluted DealWithTheDevil schemes.

[[folder:Western Animation]]
* In ''WesternAnimation/AmericanDragonJakeLong'' a drop of Jake's blood is used to restore the Dark Dragon's full strength.

[[folder:Real Life]]
* A number of Islamic Scholars accused UsefulNotes/SaddamHussein of dabbling in this trope when he commissioned his infamous [[https://en.wikipedia.org/wiki/Blood_Quran Blood Qur'an.]] That said, [[EveryoneHasStandards even those who didn't believe in magic were disgusted of the act]]. Saddam's own rationale for commissioning the Blood Qur'an was as a means to thank Allah for protecting his regime over the decades which really ''might'' count as an attempt at blood magic, if you are feeling generous.
* In Pentecostal and Charismatic circles, the spurious Scriptural practice of "pleading the blood" takes place within their meetings, since they believe that Jesus Christ's pure sinless blood has actual supernatural power over all things earthly and supernatural.