Ars Magica is a role-playing game set in a quasi-historical version of Europe around AD 1200 with added fantastical elements, called Mythic Europe. The game revolves around wizards and their allies. The game was developed by Jonathan Tweet and Mark Rein·Hagen and first published in 1987. The current edition was written by David Chart, working for Atlas Games and published in 2004.
Ars Magica was one of the first examples of a Troupe system: early editions recommended that the players collaborate to create the campaign world and story. Each player would have an opportunity to be the Story Guide, and each player would have more than one character, so that if they felt their main character would not go on an adventure (for example, if they were busy with their research) a secondary character may be used. Troupe play has been de-emphasised in recent editions, however, and in the latest (5th) edition of the game is relegated to an optional play style described at the back of the book. Many "troupes" opt for a more traditional system with a single story guide, or have one player be the "Alpha" story guide with responsibility for the overall plot, and a few "Beta" story guides who run side-adventures.
In order to produce an "authentic" feel from having such a historical setting, the game uses medieval Latin for a number of key terms.