Rules for new houses

Hi everyone.
I'm playing a campaign in a fantastical setting, like one of those invented continents that you see on misguided medievalists Maps.

I Need some guidelines for rules to create different hermetic houses from concepts.

As I have seen them the net benefit is usually a minor virtue. Even Ex Miscellanea has a major flaw to counterbalance the major virtue that it gives.

What are some tips on balance?
Should I give only minor virtues?
Can I have alternate abilities/create new virtues et cetera without breaking it ("unbalanced" as it may already be)?


I would recommend so. All current houses gain a minor virtue.
Members of House Ex Misc gain 1 Major Virtue, 1 Major Flaw, and 1 Minor Virtue - with restrictions on the types of Flaws and Virtues, but (theoretically) summing up to a single minor virtue.

But really, do what works best for you and your troupe! :slight_smile:

You need different guidelines depending on whether the houses ought to be primarily Hermetic or primarily Fantastic.

Look first at Bonisagus, Flambeau, and Jerbiton. What makes these houses interesting is their culture and not the mechanics. The players is free to select the house virtue as long as it is thematically correct. More often than not, the magus will have more than one virtue which could have been the house virtue. Mechanically, the essential rule is one free virtue. Your challenge making a new house is only to make the theme. (Tytalus and Guernicus are more constrained, to a single virtue, because the theme is a bit more narrowly defined. One can go that way if the theme requires.)

Ex Misc is the odd one out, and it is odd because the house is only semi-Hermetic. In a fantastic campaign, you may very well want to split the Ex Misc lineages into separate houses. New Ex Misc lineages are permissible even under canon, and you could make your own houses using that ruleset.

The mystery cults are harder. You need to design not just the starting character boons, but the entire portfolio of mysteries. The starting virtues are custom made, and most of them have a flip side. However, there are rules for making mystery cults, so you just need to use that ruleset if that's where you want to go.

Tremere is another oddity, since they have boons and challenges which are not captured in virtues and flaws. Mechanically they have the minor magical focus, like everybody else. However, they have the entire social structure which means they do not have their own sigil, and they can expect both help from and obligations to the house. Essentially that's an invisible minor story flaw. If you actually play this out, playing a Tremere becomes very different from playing any other house, with absolutely no mechanics to tell you. That's another possible direction for your custom houses.

What themes do you have in mind for your custom houses, @Nolzur?


I would look first towards thinking about what each house is supposed to be doing in the setting. As loke said above, the houses in Ars Magica are interesting because of how they fit into the setting. Figuring out what time each house is supposed to play on the order will help guide you along every other step of the process.

Mechanically speaking, I would probably look at like Bonisagus/Flambeau/Mercere/Tytalus/Jerbiton as a good guide. I think if you want to avoid anything really game-breaking or some kind of trap option, I would avoid doing what Ex Miscellanea does or what Tremere does. Giving a major virtue as part of a house is pretty strong, even if it's balanced by the corresponding major flaw. That kind of stuff is a pretty easy way to open your game up to big mechanical power imbalances if that's something you're looking to avoid.

Tremere, on the other hand, takes up a character's magical focus. Since a character can only have one magical focus, that is a pretty big limiter on the kinds of characters that house can produce. If you want to keep all the options for houses equally open, you should avoid having houses give a "one-of" virtue. Otherwise, you should just go the Tytalus route and just have a strictly beneficial virtue.

For Mystery Cults, I think the most interesting option would be to use The Mysteries: Revised Edition and maybe Houses of Hermes: Mystery Cults to make up your own Mystery Cults that fit into your setting.


OTOH, if you are creating an Order in which all the houses are much more distinct based on their lineages I see no problem with every house granting, as ex Misc does, a Major virtue, a Minor virtue, and a major hermetic flaw. One could imagine the houses at the beginning of the Order were more similar to this kind of makeup with each house having had much more influence from their founder’s previous lineage. One should still watch for game balance effects.


I think the main concern about Ex Misc is that the Hermetic Major Flaw has to cripple some aspect of their magic. This is what is compensated by their supernatural major virtue.

If you take (say) twilight prone, you do not limit the magic powers, and the magus can be very powerful for a long time before he starts feeling the effects of twilight.


NB! We've found Twilight Prone to be devastating in practice, though possibly the player rolled more 0s than would statistically have been expected.

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Well, for now I have:
-a faerie lineage that keeps it in the family
-a druidic cult of long lost gods
-a cult of defenders of magic places, focussed on circles
-mages from a bronze city in the desert, full of knowledge of the djinn
-rarificators of elementals, more like advanced alchemists than mages
-dragon riders, that breed weak and serpentine dragons to bound as familiars and ride like fiery knights
-a megalomaniac guild of paranoid hoarders of magic, that may or may not have made a pact with a demon to have access to forbidden knowledge

Some other things are more niche and less for players, more like plot stuff for me. @loke


Especially if you keep rolling 0 for the control roll. If you actually do control the Twilight, te character ends up with a lot of bonus elements...but also a huge load of Warping points.

Sure. But most sagas end before the huge load of Warping points start having real significance. Now, it is well known that there are different character designs which excel in the short and in the long run. Twilight Prone is a long-term flaw. Short-ranged magic in contrast is very much a short-term flaw. An Ex Misc, with the extra virtue/flaw allowance, with only long-term flaws will break game balance in the short run.

I realise that long-term is ambiguous. Twilight Prone is a long-term flaw in terms of story time, and will rarely turn up in downtime play. Other long-term flaws may kick in after long terms of downtime.

Very much agree.

Currently playing in a "fast" Saga that is north of 100 years and every point of warping is one less year a Magus will be around. All of us are fairly botch/warping resistant (by Virtues, Familiars, and Mastery). If there was a Magus with Twilight Prone it would result in ether them not making it to the saga finally or having to significantly move it up. In a saga like ours long-term flaws can be horribly crippling.

The reverse is true for one-shot or short term games, in which most of the effects of long-term flaws might not even come up. That makes them effectively free points to min-max a character with. A character with nothing but long-term flaws and short-term virtues is easily possible. In this type of game, limiting the extent to which characters take long-term flaws is actually a design requirement.


THese sound like Hermetic Sahirs, the ex misc lineage may well become a separate House.

These sound like hedge wizards to me ... making them less mages than alchemists call for several major Hermetic flaws.

It is possible that you are better off refining hedge wizard lineages than defining Hermetic houses. Most of the one-line descriptions could fit with either a Hermetic house with a slight flavour or with a completely non-Hermetic lineage with narrow-scope powers.

This could be any Hermetic House with a certain religion. It could also be a hedge tradition whose members gain their powers through worship and bargain with their gods. Finally, it could be a Hermetic Mystery Cult House which has the full Hermetic magic and mysteries on top.

It is not an easy project you have embarked upon @Nolzur. Good luck!

The specific character that @Christian_Andersen and I were referring to - the only time someone actually took Twilight Prone in a saga I've played it - had so much warping by year 19 of the saga, that the player was getting seriously worried about being able to control Twilight, even without his poor dice luck.

I think you forget my Twilight Prone Mercere I had in the campaign we played :wink: Though that was not 19years in-game long. I agree though, it is a terrible flaw!

My apologies, I wasn't tracking everybody's flaws back then. Thank you for reminding me.

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Twilight Prone can be an exceedingly bad Flaw for many (most?) magi, but there are several ways in which it can be made significantly less severe - in fact, on the lower end of the Major Flaw spectrum: From a Verditius relying solely on magical items, to a Theurgist relying on spell-spirits, to a magus with extreme bonuses controlling Twilight etc.

From my point of view, the huge problem with Twilight Prone, and Twilight in general as soon as Warping starts to be in the 5+ range, is a narrative one: it tends to happen during stories (because that's when magical botches tend to happen), and when it does it just removes the character from the rest of the story. Basically, it's often much worse for the player than for the character!

An interesting point, didn't think about it that way prior but I have to agree, now that I recall some... unfortunate occurrences in games tied to that Flaw.

This is why I think troupe style is a great idea. A character put out of play is a great narrative element, and allowing it is a great thing. If troupe play works, the player always has another servant/groom/body guard to play, and twilight makes a chance to let one of them shine.

But by all means, we have not managed to get troupe play work to its full potential either.

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Troupe play seems to highly depend on the group. Some groups hate it, some love it, and most are somewhere in the middle. Ensuring the players understand that their "main" character will not lose out on XP if they play someone else helps.

Something else that might help is running a "one shot" type adventure in which everyone plays a grog. Have them find or accomplish something that is helpful to the Covenant, such as finding books or a new vis source. Their Magi will get their seasonal XP and something else that helps them.

The speed of the game also makes a big difference. Games that are "fast" tend to be easier to engage in troupe style, since the years fly by. Slow games without much XP gain tend to be poor for troupe play since players will want to play their powerful character since they see little development. The slower the game, the harder trope play is.


Sure. Our problem is much more about having players for the secondary characters.

Part of the reason I favour troupe play is that a plausible party, especially on adventure, includes a mixture of characters and often more characters than players. In some situations the secondary characters should be primary, but we end up having magi doing everything themselves. Getting into a different role when the primary one is out of action is also not necessarily easy.