Ars Magica is a game about wizards. The magic is famously free form. At the core are fifteen arts — five techniques and ten forms that, together, form the verb/noun mechanic. The techniques are the verbs, in Latin, of course: Creo, I create; Intēllego, I perceive; Muto, I transform; Perdo, I destroy; Rego, I control. These are combined with the nouns, which cover all the stuff of creation — the four elements, the body, the intellect, animals, plants, etc. These arts can be combined to create just about any magical effect imaginable. A laboratory system allows for researching spells and creating helpful implements, which takes place during seasonal work sessions, when the character is unavailable for play.

The rules says, “True magical prowess requires native talent, long term theoretical study, years of practice, a comfortable familiarity, intuitive understanding, high confidence in one’s skills and much courage.” It is unclear whether it is referring to the fictional magic of the world, or mastery of the game’s magic system.

Ars Magica predicts a lot of ideas that would influence games in the coming decades (most clearly, it is the direct ancestor of Vampire: The Masquerade). There is no assumption that the same person takes the GM role from session to session. Players aren’t expected to play the same character session to session either. Ars Magica outlines troupe play, which encourages players to create a magus as well as an assistant, who can be played when the magus is busy with research or otherwise preoccupied. A large population of servants, warriors and such, form an additional shared character pool. These options encourage players to emphasize the importance of the overall story, deploying the characters best suited to move it forward, rather than centering the development of one favored character. As there is no expectation of game balance, with magus characters effectively as powerful as the players desire them to be, there isn’t any incentive to play them exclusively in the name of self-improvement.