Ars Magica is a ruleset for magic-centered gaming in Mythic Europe. The game is set in a Mythic Europe where the stories and legends from medieval Europe were true, or at least more true than not. Demons, saints, dragons and faeries all make an appearance, but the focus of the game is the magi, who are the primary player characters.

The game has an extensive magic system with subsystems for spontaneous spellcasting, laboratory work, enchantments and more.