In the world of Harry Potter, there are many different ways that magic can manifest itself. Sometimes it is funneled through a magical device like a wand, and other times it is made through a potion or some other kind of magical creation. The different ways that wizards are able to wield magic are interesting because the use of these different methods helps to flesh out the world and make it feel even more real and alive. There are a lot of spells that can totally transform something into an entirely new entity, which is where a subject like Transfiguration comes in.
There are some wizards that are even able to transform themselves through certain magical methods and take on an entirely different appearance. Metamorphmagus are wizards that are able to change their faces and bodies, like Tonks. However, there are also magic users that are able to transform into an entirely new species through magic, and these wizards are called Animagus. Though this type of magic is rare in the Harry Potter series, it still shows up in a few notable ways and becomes an important plot point at certain times.
What Is An Animagus?
An Animagus is a witch or wizard who is able to transform themselves into an animal and back at will. This is a learned magical skill, unlike innate hereditary abilities like Metamorphmagus have. Information on Animagus studies was taught in the third year Transfiguration class at Hogwarts, and students who were particularly talented could learn the skill during their time at school if they so chose. There was an Animagus registry that existed to keep track of those who could transform, though most of the main Animagus characters in Harry Potter are unregistered (which is what creates a lot of the mystery plots around them).
Each Animagus also displayed a particular characteristic on them that was caused by a visible trait from their human form. For example, some Animagus in their animal forms would have markings that resembled the glasses they wore as humans, or if a person was missing a limb, that would be reflected in their Animagus form as well. Wizards and witches were often able to use their animal form for specific skills, such as transforming into a small insect or animal for spying purposes, or becoming a bird to be able to fly without the use of spells or a wand.
How Does Someone Become An Animagus?
The process of becoming an Animagus was not exactly easy, and required a lot of dedication from the witch or wizard in question. The first step was to keep a single Mandrake leaf in their mouth for a whole month (the full cycle of the moon), and if the leaf was removed or swallowed, they would have to start all over again. During the next visible full moon (if the moon was covered by clouds, they would also have to start over) the wizard would spit the leaf into a vial within range of the moon's rays, then add one of their own hairs, a teaspoon of dew that was not touched by the sun or human feet for a week, and the chrysalis of a Death's-head Hawk Moth to the vial as well. This mixture was then put into a dark place and not touched for a varying period of time.
The wizard had to wait for an electrical storm, and in the period of waiting for one to arrive, chant the incantation, "Amato Amino Animato Animagus" every sunrise and sunset with their wand over their heart. When the thunderstorm finally hit, they would have to move to a secure location, recite the incantation one last time, and then drink the potion. They would then become an Animagus, and have the ability to transform into an animal at will for the rest of their lives. If any part of this very complex process was done incorrectly, it could lead to disastrous consequences, such as causing permanent half-human, half-animal mutations. Wizards also had no control over what animal their Animagus form was. They became the animal that suited them best, though a wizard's Animagus form often reflected their Patronus form as well.
Who Are The 5 Animagus in Harry Potter?
Because of how difficult and drawn-out the process of becoming an Animagus was (as well as the potential consequences), not many witches or wizards attempted to become Animagi. However, there are still quite a few that pop up over the course of the Harry Potter series. One of the only registered ones that the characters come across is Minerva McGonagall, the Hogwarts Transfiguration professor. McGonagall's Animagus form is a cat, and is in fact one of the first characters that is introduced in the series as she watches over the Potter's house in her cat form.
Rita Skeeter is also an Animagus, which is revealed at the end of Harry Potter and the Goblet of Fire. Skeeter was an unregistered Animagus who could turn into a beetle, and she used this form in order to gather intel and spy on people to get the scoop for her articles without being detected. Hermione ended up blackmailing Rita Skeeter after her horrible treatment of Harry in her articles, as Hermione threatened to expose Skeeter as an unregistered Animagus, which would have led to huge legal consequences.
Perhaps the most well-known Animagi in the series, however, are the Marauders - specifically James Potter, Sirius Black, and Peter Pettigrew. These three became Animagi during their years at Hogwarts in order to support their friend Remus Lupin, who was a werewolf. As Animagi, they could accompany him during the full moon without bringing harm to themselves, and they prevented him from becoming very violent in his werewolf form. James had the ability to turn into a stag, Sirius a dog, and Peter a rat. Sirius and Peter's Animagus forms become important again during The Prisoner of Azkaban, when Sirius showed up on the school grounds as a dog and the characters discover that Peter had been hiding as Ron's pet rat Scabbers for the past 12 years. The Marauders are some of the most iconic Animagi as far as the fandom is concerned, since their transformation was such an integral part of their story.