An Encantus is a textbook of magic and spells. These books typically include instructions on how to perform supernatural charms, spells, and also how to create magical objects such as amulets and talismans. An Encantus is considered a magician’s guideline that teaches sorcerers the art, history, and science of sorcery.
According to Balthazar Blake, it is revealed that there have been many copies of the Encantus given to many conjurors, especially those on both sides like the benevolent Merlineans and the Morganians. Balthazar gave David Stutler one of them. When he did, it was a small "pocket addition," but then Balthazar unfolded it into a huge thick book.
"The Encantus is our textbook. The art, science, and history of sorcery. Including our recent history as well." - Balthazar Blake about the Encantus.