The user can transfer their blood into another individual's, or taking blood from another person into oneself. Depending on the properties and the contents of blood, transferal can any number of unique effects.
Haruto Kurosawa (Coppelion) giving his healing-enriched blood to an injured Kanon Ozu, enhancing her healing factor.
Jedah Dohma (Darkstalkers) can lethally supplant his demonic blood into others.
Utsuro (Gintama) giving his life-enriched blood to a dying Oboro, bringing the child back to life. However, Oboro's mortal flesh is breaking down from the blood's power in the long term, and its immortal attributes are only prolonging his suffering.
Carol Danvers/Captain Marvel (Marvel Cinematic Universe) was transformed into a human-Kree hybrid after being transfused with the blood of Yon-Rogg.
Jennifer Walters/She-Hulk (Marvel Comics) gained her powers after receiving a blood transfusion from her cousin, Bruce Banner.
Eli Bradley/Patriot (Marvel Comics) received powers reminiscent of Captain America's after receiving a blood transfusion from his grandfather Isaiah, a participant in Project Rebirth.
Wade Wilson/Deadpool (Marvel Comics) was transfused with Wolverine's blood by the Weapon X program, granting him a healing factor on par with Wolverine's.
Jacqueline Falsworth/Spitfire's (Marvel Comics) X-Gene activated through a combination of being bitten by the vampire Baron Blood and being transfused with the artificial blood of the synthezoid Jim Hammond/The Human Torch.
Instead of being killed like his Earth-616 counterpart, the Benjamin Parker of Earth-91918 (Marvel Comics) survived being shot thanks to an emergency blood transfusion from his nephew Peter Parker, which in turn gave him Spider-Man's powers.
Robert Frank/Whizzer (Marvel Comics) was transfused with the blood of a mongoose by his father to save him from a cobra bite, activating his latent mutant ability of super speed in the process.
The Body Adaptation Machine (Metroid) is a device created by the Chozo to infuse other beings with their blood, giving them a better chance of adapting to other planets' environments.
Samus Aran (Metroid) was transfused with Chozo blood at a young age, granting her great physical strength and athleticism.
Moka Akashiya (Rosario + Vampire) injects her blood into Tsukune Aono through her fangs.
Tsukune Aono (Rosario + Vampire) gained vampire powers after being transfused with Moka Akashiya's blood.
After being heavily injuried in a mission, Saki Amamiya (Sin and Punishment) was transfused with the blood of Achi, allowing him access to a Ruffian form.
Takuya Yamashiro/Spider-Man (Spider-Man Toei) was transfused with the blood of Garia of Planet Spider, granting him spider-like powers.
Sam Winchester (Supernatural) is one of several "special children" who was fed Azazel's demon blood as a six month old infant, granting him demonic powers.
The Leviathan Edgar (Supernatural) injects his blood into an angel, with deadly results.
After being stabbed, Jennika (Teenage Mutant Ninja Turtles IDW) was transfused with Leonardo's blood, causing her to become a mutant turtle herself.
Uber Reptiles (Ty the Tasmanian Tiger) are the result of Boss Cass transfusing mammal blood into his reptile henchmen, mutating and empowering them.
By drinking the blood of Alexander Corvinus, Selene (Underworld) gained increased vampire powers and an immunity to sunlight.
Marius (Underworld: Blood Wars) transfused himself with the blood of Michael Corvin, turning him into a powerful Lycan-Corvinus Strain Hybrid.
Chiba Yuusaku (Wolf Guy - Wolfen Crest) received a blood transfusion from Akira Inugami, causing him to become a werewolf.
Beast Boy (Young Justice) received a life-saving blood transfusion from Miss Martian, granting him shapeshifting.