Ars Magica

Ars Magica is a role-playing game set in Mythic Europe, a quasi-historical version of Europe around AD 1200 with added fantastical elements. It typically centers on the lives of Magi, powerful wizards belonging to the Order of Hermes, and the various mundane folk in their lives. While several details about the world change, sometimes drastically, from edition to edition, the same basic premise applies: the Order is a secret society in a world that believes in magic, founded by the apprentice of a wizard who first developed a unified magic theory and a general defense against magic, the Parma Magica. There are twelve Houses (with a missing thirteenth), each focusing on a particular area of study that the House founder excelled in originally:

Bjornaer: Shapeshifting magi who can change into form of their "Heart-Beast" (or, in the case of an inanimate, natural object, a "Heart-Shape"). They are descended from a Pomeranian Bear-witch name Birna and practice secret magical rites at their Domus Magnus Crintera every twelve years

Bonisagus: The Founder of the Order, though his apprentice Trianoma did most of the leg work. Originally wrote the Bonisagus Magic Theory, which is the magic system the book uses and that all Hermetic Magi are expected to know, if not use. Those who consider themselves Followers of Bonisagus are more interested in the study of magic; the Followers of Trianoma are more politically-minded. Either way, they have a natural prestige within the Order due to their Lineage.

Criamon: Magi who pursue The Enigma as the path to true wisdom and power, often prone to prophecy and using unusual logic to solve puzzles and riddles. Most insist that the Order is doomed on one level or another.

Diedne: Druids who were virtually wiped out during the Schism War and tend to be terminated with extreme prejudice even now; early editions simply mention the house as existing at one point, but they provide no information beyond "You cannot play a member of House Diedne" and a Flaw that means Quaesitors suspect your predecessors of being Diedne. Later editions provide rules for Diedne Magic, and detailed history regarding the causes of the Schism War itself (suspicions of human-sacrifice and devil worship, coupled with the house's insular and secretive nature).

Ex Miscellanea: Originally created as a "rival Order" to the Order of Hermes, but it didn't quite get there. Most of its mages only nominally practice Hermetic Magic, and is home to several "converted" hedge-wizards. Most (but not all) members do practice Hermetic Magic, albeit coloured by their earlier training, but as members of the Order they are taught the Parma Magica.

Flambeau: Battle-hungry pyromaniacs who love fire and warfare; probably the most mercenary of the Houses. Later editions have down-played the pyromania and homicidal, with mixed reaction from fans of the house. Many members of the house specialize as Hoplites (

Guernicus: Also known as House Quaesitoris; Order-keepers and judges, effectively the police. In later editions Quaesitors may come from any House, but Guernicus magi still tend to predominate due to their specialization in Intellego and Terram magics.

Jerbiton: Socially-oriented mages who love things like high society, the arts, and the Church. Most of the House's apprentices are acquired from noble houses, and sometimes even retain their mundane lives once out of apprenticeship.

Mercere: Primarily messengers and the Hermetic equivalent of the Pony Express; most of the House is comprised of mundanes. The Founder Mercere lost his Gift and took up the useful position of messenger. The Gifted members of House Merecere tend to focus on the arts of Creo and Muto and frequently possess the Mercurian Magic virtue.

Merinita: Split into two camps the same way Bonisagus is, with Followers of Merinita focusing on Nature magic, and Followers of Quendalon focusing on Faerie magic. This gives them some trouble, as molesting the Faeries is against Hermetic law. In addition to giving them access to unique RDT parameters, Merinita magi are less inconvenienced by Faerie Auras than other Magi.

Tremere: Rigidly hierarchical and focused strongly on various aspects of war, especially strategy, and notorious for moving sheer numbers across tribunals to gain the majority vote in order to block unfavorable laws from being passed. They operate under strict codes of dominance and submission, and often not considered trustworthy by the rest of the Order due to their trying to take over the Order. They are usually written as the primary instigators of the Schism War.

Tytalus: The Trickster House. Tytalus philosophy states that only conflict can inspire growth, and so they constantly test themselves (and others, whether they like it or not) in various ways, sometimes referred to as The Game. This eventually led to the House's corruption when they tried to outwit the Devil, resulting in widespread diabolism.

Verditius: Natural artificers who are inept with Formulaic magic, requiring casting tools where other magi of the Order need none; they produce most of the magic items in the Order and are the beating heart of its economy.

The Order of Hermes itself is richly political, with laws governing how Magi must conduct themselves toward each other while at court (Tribunal) and just in general, with secrecy and the right to power being primary tenets of the vow taken by mages at the completion of their apprenticeship.

It 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. The game was developed by Jonathan Tweet and Mark Rein·Hagen of World of Darkness fame and if you look, you will find traces of Ars Magica in the Classic WOD - particularly the Order of Hermes mages and the Tremere vampires. The magic system of Ars Magica is generic, based on a combination of Forms and Techniques (to create fire, you'd use the form Ignem for fire and the Technique Creo for create together) and very intuitive. It's also one of few magic systems that allowed for spontaneous spellcasting, allowing the player to use magic off the top of their head to perform specific tasks, rather than limiting magical ability to a shopping list of immutable conditions and effects.

Tropes used in Ars Magica include:

Beware the Superman: Mages are well within their rights to torture Muggles to death.
- They have one Crime for this, loosely referred to as Interfering with Mundanes. No wizardly court on the planet will convict you for less than bringing actual harm to other mages, however, and not even then if you have enough political power to stop it.
Cloudcuckoolander: Criamon. In later editions, they're the only ones who have access to the Enigmatic Wisdom Virtue, which gives bonuses to understand things that normal logic can't process. The classic joke?

How many Criamon does it take to light a candle?
Fish.

The Commandments: The Order of Hermes has a Code of Conduct which (among other things) forbids dealing with demons, endangering the Order, interfering with secular governments and spying on or killing other mages.
Elemental Powers: Aquam, Auram, Herbam, Ignem and Terram spells.
- Elementalists, as described in Hedge Magic, are another (more limited) example of this.
The Fair Folk: The Faerie Realm contains all manner of different things, many of them easily offended and dangerous; this is the reason why "I will not molest the faeries" is part of the Oath of Hermes.
Flat Earth Atheist: The briefly included Realm of Reason was based around skepticism about the existence of the supernatural, despite there being clear evidence that it truly existed. The implication is that magic can only exist where it can be believed in, and progress into Reason eliminates that possibility: this is explicitly a world where weasels give birth through their ears and where amber is formed by bobcats urinating on rocks.
Functional Magic: Basically every type can be found in Mythic Europe somewhere, though the Order mainly has the Inherent Gift, Rule Magic, and Device Magic.
Hermetic Magic: Played with in a couple of ways: the only Hermetic magic as-per the trope is Verditius magic, which requires casting tools and considered a flaw of House Verditius (in some editions), and Ritual spells, which require the use of crystallized magic energy called vis and a long casting time; the rest of Ars Magica's magic is closer to Vancian Magic, but it's named Hermetic Magic after the Order of Hermes.
I Know Your True Name: Mages eventually end up with three names. Their True Name (the one given to them by their parents at birth), their apprentice name (used by their master during apprenticeship) and then the Hermetic Name (which they choose for themselves after their apprenticeship is complete). This is all because the True Name is an extremely powerful weapon in the hands of one's enemies, particularly non-Hermetic ones. Demons are especially susceptible to the use of their True Names, and invoking a Demon's true name against them usually doubles the effectiveness of whatever spell or command is being used. In 5th edition, knowing the True Name of a demon (or angel) counts as an ability and forms a powerful (x5) Arcane Connection to it. It should also be noted that, according to Realms of Power: The Divine, a character's Baptismal Name cannot be used as a Sympathetic Connection
Kill It with Fire: The Flambeau approach to most things.
Large Ham: one of the advantages of playing a 'grog' as opposed to a major character, according to the 5th edition rulebook, is that it's acceptable to chew on the scenery a little.
Magic A Is Magic A
Medieval European Fantasy, The game is actually a fantastic medieval Europe, with the typical campaign starting spring A.D. 1200 but oddly it more subverts this trope that supports it, due to the level of detail and 'reality' the various campaign source books looking at medieval politics and society. The supplement books that don't focus on the Order and its magic are about as accurate and informative as any regular general-history book, 4th edition's Ordo Nobilis in particular.
Mystical Plague: The spell "Curse of the Unportended Plague" starts a plague in a city over a period of 6–12 months.
No Eye in Magic: Some spells have the range "Eye", which means the mage must make eye contact with the target for the spell to take effect.
Our Werebeasts Are Different: Includes were-bears and were-lynxes.
Point Build System
Robe and Wizard Hat: House Mercere, commonly called Redcaps because they wear silly-looking red pointy hats. The robe is optional, but common, since most major places know not to mess with the guys in the doofy red stooge cap—those guys have friends.
Shapeshifter Mode Lock: Mages who remain in animal form too long can have their human personality replaced with the animal's.
So Beautiful It's a Curse: The Curse of Venus flaw, which makes the character very attractive to people he or she does not WANT to attract, and who won't take no for an answer.
Soul Jar: The "External Soul" virtue in the Lion of the North supplement.
Spontaneous Weapon Creation: The spell "Tooth of the Staff" can create a spear with a polished flint head. Several such spells exist, and magi can invent new ones, or make them on the fly.
Sympathetic Magic: Specifically referred to as the Law of Sympathy.
"Well Done, Son" Guy: Arguably what makes the Tremere as dangerous as they are; they are ALL Well Done Son Guys, out to please no one but their parens (the mage who trained them), who wants to please their parens, who wants to please their parens...
- Also carries over into the Tremere clan of Vampire: The Masquerade. There's no official link between the World of Darkness and Mythic Europe, but it's fairly obvious where to connect the dots. Ceoris, the center of Clan Tremere's politics, is not a happy place. Of course, Clan Tremere's origin is canonically House Tremere of the Order of Hermes... whom the clan exterminated to the last during the Middle Ages.
Witch Hunt: The reason the Order of Hermes is a secret. While most people in Mythic Europe don't think too hard about the occasional wise woman who lives in the woods or weird magician in a tower, the idea of open conflict between the Church and the Order is a headache no one wants to deal with.
- The Church is cognizant of the Order and prefers to leave it alone. It's not so much a secret as it is something that isn't widely bandied about. The Church know that the mages can wipe them out if angered enough, so they ignore them. The Order know that God can wipe them out if angered, so they leave the Church alone. It's a beautiful balance of power.
- The Order of Hermes also enforces it's own "Join or Die" policy with regards to other magical traditions; though admittedly this is rarely invoked unless the other tradition has somehow learned the secret of the Parma Magica or some similar means of Magic Resistance...