Harry Potter-ing Ars Magica?

I can do whatever with the setting, but I'm wondering how to make the mechanics match more closely.

I was thinking that the main thing to change would be requiring all magi to be a sort of Verditius-Ex Miscellanea hybrid, requiring casting tools (in this case, required to be a wand) and getting the Weak Spontaneous Magic Flaw for "free" in exchange for getting a free Major Virtue pertaining to your special wand (which, I figure, will be similar to a Faerie "Grant" item, containing numeric bonuses to certain things as well as being able to store Minor Hermetic Virtues, making it a powerful item for its wielder indeed) and a free Minor Virtue giving you either the Items of Quality Mystery or perhaps something like Method Caster that boosts your casting total on account of your wand channeling your magic. With using magic sans a wand made extremely powerless (indeed, wandless magic is possible but highly difficult and much weaker in Harry Potter) and all magi being forced to use a wand, things become rather similar indeed.

Other changes that might need to be made... Perhaps a Breakthrough has been achieved by this point in time allowing the teaching of Arts in a classroom setting? If so, you could even realistically shorten the apprenticeship to the seven years that magical institutions teach for in the Harry Potter books; although the "apprentices" will only be taught for one season a year by any particular magus, there might be specialists of different kinds teaching them different things from season to season. Sure, this removes the benefit of taking apprentices from the potential teachers, but if all magi can be trained in one school, there won't need to be a whole lot of teachers anyway, so there will surely be enough willing to take a season out of each of their years ensuring that the next generation of magi is fully taught.

Based on the guidelines in Apprentices, and factoring in the lack of +6 SQ since the students are not being taught one-on-one, the average SQ for each class season will be 7. 74 is 28 xp plus 4modifiers per year; we'll say 4, since those modifiers only apply (and for that matter would be a really huge deal) if the apprenticeship is played through. 287 is 197... Hm. Okay, so 7 years isn't quite long enough to get a real education... Unless the requirements for teaching credentials are bumped up? If the people usually reserved for "Skilled Parens" are the teaching magi in this situation, the Source Quality gets bumped up to 13. 134 is 52, 52*7 is 364... Teach them 120 levels of spells as usual on a 1 xp to 1 spell level ratio, and you've just about got the standard apprenticeship's worth of everything. Sweet. I might want to boost that up a lot, actually, because Harry Potter wizards focus on a lot of practical skills alongside magic, but this is one of those stylistic choices I'll find myself prattling on about throughout this post.

As more of a way to stay true to the Harry Potter's style, I think it might be a good idea to have the Master of (Form) and Extractor of (Form) Vis Virtues (all 20 of them, yes! All from RoP:M if you're wondering) integrated directly into Magic Theory and cut down on or completely remove vis from the equation. Okay, maybe not completely remove... It doesn't exactly work to have magic items cap out at level 20. But at the same time, enchanting items in Harry Potter is more of a "pouring yourself into the item" sort of deal, and given how much the Harry Potter series focuses on the magic being within the character and their wand, finding little puddles of magic in slain monsters or growing out of special locations just seems... Sort of wrong. I mean, it can totally work, and since a school (or covenant, of course; this will still be somewhat like Ars Magica after school's done) like Hogwarts or Beauxbatons or Durmstrang would certainly exist within a rather strong Magic Aura (there are no mundanes around within the school itself in most cases, though they'd likely farm or engage in whatever method of acquiring currency the school employs just outside the Aura) they could probably just farm the vis needed for any item enchantments... Though that might be a rather time-consuming approach depending on how far over your Fatigue limits you need to go. I'm on the line about this one; give me some opinions.

Importantly, wizards in Harry Potter neither had Magic Resistance nor any trouble dealing with mundanes, as mundane "infiltration" was often necessary. That may not be the case in Mythic Europe, of course; indeed, given the rules already available in Ars Magica, it'd be simple enough to replace HP's Wizard Duels with Certamen and accept that they'll be outcasts in most societies for more reasons than just frequent Turbulences. The bigger concern, here, is that with the new school-based magic teaching system, all the students would probably be too busy hating each other to learn anything, especially when group work is required. I was considering two possibilities. Either Parma Magica could be moved to earlier points in the teaching schedule, so the students could protect themselves from the negative effects engendered by each other... Or, simply to follow HP's canonical wizardry more closely, give everybody the equivalent of the Gentle Gift, and quite possibly remove the Parma Magica entirely. However, while removing Parma helps keep true to the series in and of itself, it comes with unfortunate implications given how the rest of how magic scales in Ars Magica. Spells similar to HP's "killing curse" are achievable at such levels as 40, and can be cast successfully (with Fatigue) at casting total 30. With no need to penetrate a Parma, it would become WAY too easy for characters to kill each other quite early on, while such magic is illegal and, more importantly, extremely difficult in the source material. Normally I'd disregard it, but the difficulty in killing adversaries is a huge part of HP's spirit, so I'm... hesitant. I was considering applying a houserule that I saw mentioned before, with Parma providing a much smaller general magic resistance but giving a huge boost to defensive spontaneous spellcasting (which would be necessary to make defensive spont'ing even plausible here, since everybody has Weak Spontaneous Magic...) equal to 5 or even 10 times your Parma Magica score. Even MR 0 prevents atrocities like casting total 30 kills, so... Opinions on the whole Gift and Parma Magica things?

Eh... Potions is an entire class in Harry Potter... Perhaps I could also have either Mythic Alchemy or, probably more accurate to HP, Single-Use Charged Items (a Learned Magician integration possibility, HMRE) already incorporated into Hermetic theory?

There are actually a lot of interesting parallels between the Ministry of Magic and the governing structure of the Order of Hermes. I probably won't have to change much at all in this regard, really. The Ministry is more aristocratic than the Tribunal system, and the Ministry's laws are a fair bit stricter, but overall they are very similar systems and the Code can pretty much stay as it is.

Another big concern, for me at least, is Warping, specifically Twilight. It's probably going to just be one of those things that's different between the novels and the games; even in HP Ars Magica, Longevity Rituals are still extending lifespans and magi are still going into Twilight and generally ceasing to exist for brief periods and hopefully coming back later with more or less knowledge. The whole Realm Warping, not to mention the Realm divide, interacts somewhat weirdly with HP, even, but a lot of it could be explained away with a simple change in terminology, so I don't really mind it all that much I guess.

I can't really think of anything else to change to turn Ars Magica into a believably Harry Potter world, myself, though there's this itch in the back of my mind that I thought of something really important before and forgot it while writing other stuff.

So, what are your opinions on the changes I've considered so far? Any suggestions for more things to change? Explanations of how stupid an idea this is and how I'm ruining the best parts of Ars Magica? Alternatively, exclamations of how fun this seems and encouragement for me to try to solidify this? Angry criticism of my poor third-language English writing skillzorz? Anything else you feel like saying after reading the ideas I'm tossing around about how to Harry Potter-iffy a variant Ars Magica setting, mostly just by changing how the Order of Hermes works (and not even in necessarily drastic ways, partly because I don't want to write a bunch of new rules for this)? If you have answers aside from "no" and "don't care" to the above questions, please voice them! Thanks in advance for any responses, whether they be encouraging, discouraging, criticizing, or even just blabbing about your feelings on anything I've written. Just as long as you don't intentionally troll, because, y'know, trolling. :angry:

EDIT: Upon second thoughts, there is Form resistance. And a standard curriculum would by necessity result in a vast majority of generalist magi. Maybe Parma isn't necessary for defense of the self...? Hm...

What's your goal here?

Ars seems to be a good fit for the Potter setting because it does description of the magic and individualization of magical abilities much better than anything else ever written (at least that I've seen). Stuff like Voldemot's splitting his soul into the Horcruxes and the existence of the deathly hallows feel just like mystery initiations do. On the other hand, this descriptive power of Ars Magica makes it a challenge to fit with another setting (like the potter books) because -everything is described already, and it's described differently.

So while it would be fantastic to make a modern hidden magic setting using Ars Magica that evokes the feel of the potter books. It is a pain to copy things slavishly because you have to go through the work of copying things slavishly.

Is it important to have your characters meet the Weasleys and ride thestrals? Do you want to move on in the story after the period of the books (to me it looks like the big story of the setting has already been told) or do you want to retell the story with different characters and see how it comes out differently?

I'd be tempted to run a Harry Potter like game using Ars but I would not be tempted to do what you're apparently planning on and pound the two things into one amalgamation with Potter unaltered on top and Ars Magica pruned and twisted to fit into it. That looks like too much work.

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There's a lot to digest..

I'm running a saga (Stealing the Future) based on breakthroughs related to teaching the Hermetic Arts to more than one student at a time, and also a breakthrough that the Aegis suppresses the effects of the Gift. So, there is some similarity to Potterverse, that it happens at a school. I have compressed the educational period down to 7 years, but there are some significant house rules in doing it.

Like Erik Tyrell, I wonder what your goal really is?

It's variable, depending how you interpret the HP books, honestly.

I resorted to declaring that each spell is an ability of level equal to it's magnitude, and thus, had to be learned that way.

Of course, HP's wizards can do things Magi can't, and the inverse. They can manipulate regios, magi can go "Awww, a killing curse, how cute. Oh look, you're on fire, and coated in sticky oil."


Running a bildungsroman in AM is relatively straightforward. Children discover they are wizards, come of age, face unexpected threats... The online HBO Ars Magica series is an excellent read and looks like an excellent game in this style. Well worth your time, even if you weren't looking to run in the same genre.

But if you want Harry Potter style....

All spell are aimed. Dex+Finesse. There is no Parma Magica "shield" but lots of fastcast defenses. Even a mundane dodge can do the trick. (And most wizards never get very good at aiming or reacting quickly.)

Area effect damage spells seem to be non-existent, or nearly so.

HP wizards specialize. This is probably the most important feature, thematically. In Book 1, when Dumbledore says he could never have Voldemort's power and McGonagall says it's because he is too noble, the obvious meaning is that she is saying that he would never actually use Dark magic. But really, she means that he has the power but lacks the capacity. The kind of magic you do is based on who you are and who you are trying to be. The Weasley twins are phenomenally powerful and inventive when it comes to prank and humorous magic, world class really; even the MoM buys their stuff and militarizes it. That's who they are, truly madly deeply. Their magic reflects this.

AM wizards can do any Hermetic Magic; HP wizards often have limited capacities.

I think this is the hardest thing to get right.

Another feature of HP (that might be undesirable in a game) is that the last 3 generations of wizards were a lot more capable than this generation. The Potter gang (with Harry's dad) could whip up an entirely new kind of item, the Marauder's Map. (Note that no one else has one; "Moody" doesn't create one for himself or even make a copy.) Snape invented new spells in the margins of his potions textbook, which he also corrected. Voldemort? We know about him. And before that Dumbledore+friend. Harry's gang isn't up to that, not even Hermione.

I think that spontaneous magic does exist, but not for everyone, especially for spells that are difficult for a particular person: These can be cast, but only with lots of practice. Hermione knows many, many spells, but I see this more like learning Arts quickly: She does not need to spend a season learning how to say Reparo!

But as other posters said, it all depends on what you want.

I think that adapting something like Smallville for HP would hit closer to the mark.



It will definitely be a challenge, but I am sure with some twist, you can find solution. It all depends on how faithful you want to be to the books.

First, there is no more the 12 Houses, but there is some Mystery cults (Voldemort, the Phenyx society...). So get rid of House free virtue/flaws. They might still exist, but more like an old tradition, a family secret, a bloodline traits.

Second, there is obviously no Parma, but a lot of fast cast defense and if you want to follow the book a lucky beginner can - at least briefly - have the upper hand against an senior expert. It all depends if what are able to do the heroes (HP gang) can be done by everybody or it is the exception. Obviously, it brings the topic of easy killing spell. Considering that at some stage, Harry Potter is about to cast a deadly spell on an opponent (I don't remember which book), it shows that they can even been learned by low level magus. What prevent magus to kill each other (beyong the MoM) is a stain linked to practice black magic. Ways to rule that is Black Magic and deadly spells required to perform some Chtonian ritual (without virtue need) - getting the equivalent of a negative Twilight Scars.

Although, for the sake of power curve, I would consider that what does Harry Potter and Hermione are the stuff of legend and should not be the benchmark for young magus. Or Confidence point can be used for magic and they had a lot of them ? Each confidence point can be used to get a +5 boost to casting ?

Third, learning spell is incredibly easy. So there is Faerie virtue (Faerie-Raised magic in HoH: Mystery cults p86) which allows to learn spells by watching them being cast, which must have been integrated into Hermetic Theory. If you consider that attending class gives a pool of XP, and professors are performing in front of their students, they can use said XP to learn spells that way. Characters like Hermione must have virtues like Independent study and book learner which gives them access to a larger pool of XP or a rebate on spell xp costs.

Fourth, either there is no gift penatly (but you can argue that Harry Potter suffer from Blatant gift considering his childhood) or mages have ways to mitigate that since they live amongst muggles quite effortlessly.

Fifth, Magical items seems inconsistant: a cape of Invisibility is seen as an incredibly rare item, but floating candelholders are abundant (probably minor items).
One way to try to fit that in Ars is allowing Ritual and lesser items not to need virtus anymore (or it can be replaced by some mystical components), however invested items still needs it and virtus is extremely rare and possibly cannot even be extracted. So simple minor items are relatively abundant, but invested items with powerful effect are not (and you probably need to ban focus or rewrite it, otherwise some mage will be able to make powerful lesser items breaking the HP paradigm).

Finally, HP paradigm is breaking some Ars limit: it is possible to do a form of time travel (Hermione is granted a pocket watch which allows her to attend two classes in book 4 or 5), so it is clearly breaking an hermetic limit. Also the spell power scale is clearly different: everybody is able to teleport, but only from chimney. Maybe an integration of Potent magic into some specific spells granting huge bonus for TP ?

  1. Spont magic always divided by 5. You need a minor virtue to be able to cast it in the first place. there are very few instances of spont magic being used.

  2. Easy formulaics. 1XP per magnitude of the spell to learn it. So if you have 10XP experience source you could learn 5 level 10 spells in a season, for example. hermione has a virtue to grant more XP here.

  3. The thing said about no parma and fast cast defences is true. However, you can also change it to a plain attack/defence combat stat if you want to. Since voice is required to cast magic, the identification of Te+Fo is automatic. In fact I think this (using a basic combat stats block) fits better on how magical combat is performed in the HP books

  4. item creation is tricky since nowhere in the book we see how they are created. We know that most items are unique, though. Only brooms, wands and the like seem to be common (and they are hardly ever exactly equal). Seems people can create items that fit their magic, though. The clock of Mrs Weasley for example is "motherly stuff" and voldemort's items are "wicked bad guy stuff".

  5. you get a Focus in your character concept. If your magic fits, you get the boost. Much more general than usual focuses.

  6. Elves are masters of magic. Going toe to toe against an elf is a bad idea.

Offer an alternate method of learning a spell, where you learn it like Virgilian Wizards, as an accelerated Ability. This represents learning it by rote and practice instead of by understanding the deep structure of the spell.

Given a sufficiently good wand-bonus, you can still cast spells of the 1st and 2nd magnitude reliably after just a few days(ie, one xp) of study, and have some hope of casting a spell of the 3rd and 4th magnitudes. You don't get the TeFo bonus to casting, of course, since you don't really understand the spell.

I'm actually thinking of doing something like this in 1220 Ars Magica, as a result of improved alchemical knowledge(the better to make wands with!). Older magi tend to hate it, but it's an effective shortcut if you want to learn a bunch of low-level utility spells that you aren't planning on casting in combat or other adverse conditions.

(Yeah, it's a potential trap for players: "Sure, go ahead and make yourself dependent on a casting implement for significant swathes of your magic! That won't come back to bite you at all!")


Interesting. So the idea is to have a massive bonus for your wand talisman (like +8-15 to cast spells). It is another approach, certainly. Will have to consider it.

Yeah. It let's you keep much of the system intact while still being in the style of Harry Potter(albeit not exactly the same). Everyone is studying the Arts, which is where all the reading and essay-writing comes in, but for magic that the kids get to use in the here-and-now, you have spells that they can learn in a very shallow fashion. (And apparently Hermione has Flawless Caster, Good Student, and Learn From Reading, since she can pick up spells faster than anyone.)

I also recommend adapting the Rusticani enchanting rules, because combining that and charged items is probably the best way to have both fast-brewing potions and Weasley Wizard Wheezes.


As an accelerated ability certainly. But allow characters to take an affinity with the types. (group them by type, as the books do. Transfigurations, Charms, Conjuration, Hexes and Curses are the ones I remember off the top of my head. Transfigurations are akin to a mix of muto and rego, charms are creo when imaginem, often rego for other things. Conjuration is creo-objects, hexes are effectively duration possessing offensive effects while curses are duration momentary equivalent offensive spells (Blasting hex, anyone).

Main thing to remember is you can separate magic defences into 3 types.


In Ars Magica, the Parma is passive. It works once it's up as a forcefield, essentially. The magus doesn't need to move it or use it actively to stop effects.
Rego wards are Reactive. Once established, they are passive, but you need to know to put them up for them to be useful.
In Harry Potter, the shield spell is active. You need to know to put it up AND to put it between you and the offensive event. In addition, there seems to be differing types based on what they shield against. I'd suggest making it "Pick 4 artes, it protects against effects from those artes and nothing else, up to magnitude X (where Magnitude X is defined by the base level of the spell)

Other things I would suggest is that an older caster tends to be stronger. Maybe make the spells semi open-ended? So you learn the baseline stunning spell. But if you keep putting XP into it without using it for mastery (which I would allow. Snape's attempt to teach silent magic in 6th year is very 'mastery') you can increase the base guideline. So, for example...

(Using elements from The Mysteries Revised Edition, Potent Magic, modified for this. Page 31, TMRE.)

Stunning Spell (STEW-PE-FIY) ReMe 10+ (Potency Bonus from WAND +4, Potency bonus from Wand core/Wand Material SG discretion)
This spell knocks the target unconscious. At the base level of 10 it knocks the target unconscious for 10 minutes, or requires an equivalent level spell to awaken them again as a counter effect. Each additional level allows you to increase the time by a further 2 minutes, and increases the required level for a reawakening spell.
Base 4, +2 Aimed Up to 10 meters (Equivalent to voice), Momentary, Individual.

With this spell as written, you'd need to learn it to level 6, as an accelerated ability that's 21xp. After that, you're increasing it's effectiveness. Learning to cast it wandlessly would be possible once you exceed the +4 bonus from a wand, ignoring the core/material bonuses. Once that has been fulfilled, it can be learned as a mastery ability, and is especially useful when employed alongside still and silent/quiet magic.

Also, remember, Hermione might have all those. Harry has "Puissant Protective Charms" or somesuch equivalent, given he's stupidly good at a young age at the Patroneous charm and the shield charm.

Also, is it just me or are the Dementors dark fae? They do seem to be, and having to use a specific spell to drive them back seems very much the story they want to tell.

I tried one day, making one Hermetic/Magic University.

Harry has Fast Caster, and a high Dex and Qik. He has a hard time learning spells (compared to Hermione), but once he does he gets a lot of mileage out of them. So he might have FM, FFM or both. I still think Hermione and her ilk can be represented as having great spontaneous magic; Harry has to work hard because he isn't smart enough to spont well (and lacks Hermione's spont virtues?) but he has a toolkit of formulaics and excels with them. As a great Seeker, he has world class perception abilities, so he is less likely to be blindsided, and also world class athletic ability for those fast reactions and clutch moves. He probably even has True Faith (in Dumbledore, but whatever.) He also has Plagued by Supernatural Entities, and a Destiny. :slight_smile:/2

Harry probably also has a Strong Will, which helps both in casting and resisting certain kinds of magic.

So Harry can throw up shields very fast, get the first attack in, and use the simplest of spells with great effect.

BTW, "Protego" seems to work against almost anything; one shield fits all. Not the 3 forbidden spells, of course. But Imperius can be resisted with Strong Will, Avada Kedavra can be Dodged, and Crucio... Hmm... I don't remember anyone in the books resisting that when properly cast.

Hermione is much better at magic than Harry, but she isn't as fast, isn't as determined, isn't as lucky/unlucky. Dumbledore too, yet he considers Harry the better wizard because of his non-magical attributes. Character being more important than magic and affecting magic (you are what you choose to do) are themes that run throughout the series; I think getting this right in a game is most important.

Strong will again for the torture curse. Fight through the pain.

There's evidence that proto works against most forms of MAGICAL attack. Less that it's effective against mundane physical damage. We've no sign that it can be used to stop, for example, a snake. Or a dagger. Or a thrown snowball.

Otherwise third year and above snowball fights would be pointless :wink:

Follow up reply:

Turbulences (Apprentices) are pretty close to how the HP books describe accidental magic.

They'd be awesome! You'd have Slytherin's Spell of Sudden Snowball Cessation, an eldritch green snake that devours incoming snowballs versus...

Let's be fair here.

Hermetic magic is still stupidly powerful (I'm still working on my modern re-write of AM5 as a mind exercise, and my mind did wander on to 'how does this differ from Harry Potter' a few times). It can do things that HP's wizards can't. Flexible, on the fly spellcasting. Aegis of the Hearth. Parma magica, the universal magic resistance. Etc.

HP's wizards, however, can: Manipulate regios (Hogwarts is within one. The trunks with TARDIS like properties in regards to space...), create charged items which don't give the target warping (particularly obviously, anyway. Portkeys? Floo powder), teach their magic in more than 1 on 1 situations.

Animagi are Heartbeasts
I'd say a Proto shield spell's magic resistance when cast is equal to the level you cast it at. So if you learned it as a level 5 spell, it's got 5MR.
Penetration is calculated normally with regards to the skill, and arcane connections, but the penetration of spells is equal to their level? Mimics the books, where a stronger stunning spell will punch though shields?
For the unforgivables, give them a bonus to penetration as part of their design?