Nature
Chapter 3
The difference between Transfiguration and the Animagus transformation ability is that an Animagus can change into an animal whenever they want, without a wand or an incantation. Being an Animagus is an ability, and Transfiguring requires a spell. An Animagus still thinks as a human does when they are in their animal form, seeing as Rita Skeeter was able to eavesdrop on others' conversations when she was in the form of a beetle. However, an Animagus' feelings are not as complex when they are in their animal form. A Dementor's influence on an Animagus in its animal form is weaker than on its human form.
Animagi also have the ability to communicate with normal animals. There seems to be a clear understanding of want and need in this ability, but the full extent and quality is unknown. Sirius Black's Animagus form, a black dog named Padfoot or Snuffles, was able to communicate on a rudimentary level with Crookshanks, Hermione Granger's part-kneazle cat. As well, Peter Pettigrew's Animagus form, a grey rat named Wormtail or Scabbers, was able to communicate on the same level with passing rats that gave him hints and directions as he travelled around Albania in search of Voldemort. The precise form of communication is yet unknown, though it is probably not telepathy since Sirius did not know Crookshanks' name until Hermione told him.
There is a reversal spell which creates a blue and white flash that will force an Animagus out of its animal form. Remus Lupin and Sirius Black once used it to force Peter Pettigrew out of his rat form. This spell could possibly be the Homorphus Charm that Gilderoy Lockhart claims he used on the Wagga Wagga Werewolf to force him into his human form.
It is also important to note that werewolves are fundamentally different from Animagi. Lycanthropy is caused by a blood infection transmitted through the bite of a werewolf, whereas the Animagus skill is learned. The werewolves cannot keep their minds after a transformation (unless they take the Wolfsbane Potion), nor can they control themselves when they transform, while Animagi can do both. However, as werewolves only harm humans, Animagi, while in their animal forms, are safe to be in the company of werewolves. They actually help calm them down and make the transformations easier, as demonstrated with the Mauraders. Three of them transformed to help the fourth, who was inflicted with such a curse.
Animagi also have the ability to communicate with normal animals. There seems to be a clear understanding of want and need in this ability, but the full extent and quality is unknown. Sirius Black's Animagus form, a black dog named Padfoot or Snuffles, was able to communicate on a rudimentary level with Crookshanks, Hermione Granger's part-kneazle cat. As well, Peter Pettigrew's Animagus form, a grey rat named Wormtail or Scabbers, was able to communicate on the same level with passing rats that gave him hints and directions as he travelled around Albania in search of Voldemort. The precise form of communication is yet unknown, though it is probably not telepathy since Sirius did not know Crookshanks' name until Hermione told him.
There is a reversal spell which creates a blue and white flash that will force an Animagus out of its animal form. Remus Lupin and Sirius Black once used it to force Peter Pettigrew out of his rat form. This spell could possibly be the Homorphus Charm that Gilderoy Lockhart claims he used on the Wagga Wagga Werewolf to force him into his human form.
It is also important to note that werewolves are fundamentally different from Animagi. Lycanthropy is caused by a blood infection transmitted through the bite of a werewolf, whereas the Animagus skill is learned. The werewolves cannot keep their minds after a transformation (unless they take the Wolfsbane Potion), nor can they control themselves when they transform, while Animagi can do both. However, as werewolves only harm humans, Animagi, while in their animal forms, are safe to be in the company of werewolves. They actually help calm them down and make the transformations easier, as demonstrated with the Mauraders. Three of them transformed to help the fourth, who was inflicted with such a curse.
