Transformation

Transformation reflects an individual's ability to physically metamorphose their body, or parts thereof, into something else. This is usually an automatic function, governed by either the user's will, or by existing outside stimuli, such as atmospheric conditions, phases of moon, etc.

Creatures
There are many supernatural creatures that possess this ability to one extent or another, the most notable of which are shape-shifters, who can modify their entire form to resemble a different person, animal or creature.

Werewolves also possess the ability to transform from a human into a wolf-life creature and back again. This is usually governed by the precepts of a curse, such as turning into a wolf under the light of a full moon, and returning to normal upon sunrise.

Vampires are known to take on various forms, transforming into bats, or wolves or even mist. Some vampires, such as the ones presented in Buffy the Vampire Slayer, can maintain a human appearance, but when the thirst for blood is upon them, will take on a more monstrous countenance.

Another supernatural creature with shape-shifting capabilities are Maenads, which are beings of Greek origin. One such creature appeared in season two of the HBO television series True Blood. The character of Maryann Forrester was a powerful Maenad who was immortal and had the ability to transform her entire body, or selected parts into other creatures. Her chosen form of power was that of the bull, but she also turned her hands into cloven-hoofed bovine appendages.

Another type of physical alteration may come about through the consumption of certain types of food, fluids or chemicals. The most infamous example of this type of transformation hails from the Robert Louis Stevenson novel Strange Case of Dr. Jekyll and Mr. Hyde, in which scientist Henry Jekyll, seeking to develop a means to exorcise the "evil" elements of a man's soul, drinks a potion that instead brings out his evil side, which is given the name Edward Hyde. As Hyde, Jekyll undergoes a physical and mental transformation, which allows him to grow bigger, more menacing and sometimes even demonstrate monstrous physical traits.

Films

 * Abbott and Costello Meet Frankenstein - Larry Talbot into a werewolf. Dracula into a bat.
 * An American Werewolf in London - David Kessler into a quadruped wolf.
 * An American Werewolf in Paris - Multiple cultists into werewolves.
 * Dr. Jekyll and Mr. Hyde (1931) - Henry Jekyll into Edward Hyde and back again.
 * Dr. Jekyll and Mr. Hyde (1941) - Henry Jekyll into Edward Hyde and back again.
 * Dr. Jekyll and Mr. Hyde (2008) - Henry Jekyll into Edward Hyde and back again.
 * Frankenstein Meets the Wolf Man - Larry Talbot into a werewolf and back again.
 * Mary Reilly - - Henry Jekyll into Edward Hyde and back again.
 * Wolf Man, The - Larry Talbot into a werewolf and back again.

Television

 * Hemlock Grove: Jellyfish in the Sky - Peter Rumancek into a werewolf.
 * Jekyll: 1.1 - Tom Jackman into Edward Hyde and back again.
 * Jekyll: 1.2 - Tom Jackman into Edward Hyde and back again.
 * Jekyll: 1.3 - Tom Jackman into Edward Hyde and back again.

Books

 * Strange Case of Dr. Jekyll and Mr. Hyde - Henry Jekyll into Edward Hyde and back again.