A view on the Forms and the wider world

This blog post is a broad pondering the meta-physics of the forms of magic in the Ars Magica role playing game.

Instead of considering the metaphysical thinking in the medieval period – which is where Hermetic magic is meant to get its roots I started to think of a way to consider and compare the forms. This idea does not at all match to what I understand of the basis of Hermetic magic in the setting or the current guidelines. As I said, this is a pondering.

It came out of thinking about why it is easier to change some things into other things (it’s easier to change a person into an animal). Why?

What if there are a set considerations for all things:

  • Intangible vs Tangible things (eg. the mind vs trees)
  • Living vs Non-living things (animals vs rocks)
  • Changing vs Fixed things (water vs rocks)
  • Sentient vs non-Sentient things (people vs rocks)

…then it might be possible to look for how many steps from each other they are.

  • Animal (Tangible, Living, Fixed, Non-sentient)
  • Aquam (Tangible, Non-living, Changing, Non-sentient)
  • Auram (Tangible, Non-living, Changing, Non-sentient)
  • Corpus (Tangible, Living, Fixed, Sentient)
  • Herbam (Tangible, Living, Fixed, Non-sentient)
  • Ignem (Tangible, Non-Living, Changing, Non-sentient)
  • Imagonem (Intangible, Non-Living, Fixed, Non-sentient)
  • Mentem (Intangible, Living, Changing, Sentient)
  • Terram (Tangible, Non-Living, Fixed, Non-sentient)
  • Vim (Intangible, Living, Changing, Non-sentient)

And each step of difference creates a “hermetic” magnitude of difficulty when changing one to the other, or using one with the other.

Ok fine. To what purpose?

Well if Ars Magica had its time again I think it would make sense to break away from the thinking of the medieval period in the backbone of the magical laws.

Because Hermetic magic should be (and is) flawed just as the representation of the divine in Europe the setting is flawed, and many other parts of the setting use contradictions as levers for stories.

Don’t get me wrong – in the setting the characters would still try to leverage their mindsets, learnered philosophies, and all sorts of esoteric thinking in using magic “in story”, but out of story the magical meta-physical laws would be slightly different. This introduces a deliberate contradiction between the in-story beliefs and the “actual” truths.

Essentially – The magi are watching the shadow play on the wall of Plato’s cave and believe they see the real truth of magic – this demonstrates why some types of magic can do things that Hermetic magic cannot. It adds depth to the already existing contradictions in the setting and sourcebooks.

…just a ponderous post. Happy gaming.


Discussion on Mystery Cults and Virtue Initiation 

The ways that Mystery Cults grant virtues and flaws bugs me. Not because it’s broken, in fact it looks to be designed for consistency and meta-game balance, and in play it might be ok. Recently however I have been designing a number of characters using accelerated advancement as example characters and its highlighted to me that sometimes those characters have a disadvantage or an advantage based on stats and skills (Communication in particular) that are probably otherwise not relevant.

Also the sacrifice of time and resources is the most potent part of a character’s life as it represents the opportunity cost of another activity, and the choice to tell a specific story. Further I’d generally argue that resources equal time.

When the Ability + Skill + Trauma vs Number calculations are all said and done the outcome is frequently a cost which is roughly equivalent to the gains; with flavour to the story and character.

There is also a different process for gaining virtues through the magic realm whilst consuming vis which has a similar outcome with different story drivers. It also requires sacrificing something, be that vis, time, or gaining flaws.

So keep the flavour suggestions of the mystery cult, or training deal, or magical realm journey and also standardise the mechanics. Perhaps the system is better served with a simplified approach?

Putting the numbers as fuzzy as this has no play test, an approach is to make the benefits balance the costs of initiation:


  • Each minor virtue costs 15 points.
  • Each major virtue costs 45 points.


  • Each minor or major flaw grants opposite of the above. This is basically allowing a one-to-one match of character advancement to continue.
  • Each pawn of vis grants 1 point, spent or gifted or lost in whatever style suits the themes of the character and story. Perhaps the point value needs to scale to suit the rarity of vis in the saga.
  • Every initiation requires a season. This is in service to a mystic, or sacrifice, or building something, or doing favours; whatever suits the story.
  • Each additional season spent grants 5 points.

So now we have a system which requires sacrifice, places the onus on the game lore for the in-character changes, and makes building the character’s quicker and simpler. That seems like a win and it’s not overly far from the material in Ars sourcebooks.

Crying for points

A Giant Precedent, spell discussion for Magus Morat

Morat is a combat oriented Magus for a play-by post-game who is deliberately gruff and also highly focused on physical mundane combat.

Designing Morat for the game was simple as Ars Magica has many spells which enhance combat abilities on one way or another. There were too many good options so I picked a few stable spells (Edge of the Razor, Endurance of the Berserkir) and hunted one or two from outside the base rulebook.

One stood out in particular : Assume the Stature of the Giants of El Cid (MoH p.49, MuCo15). This is a spell which increases the size of the caster and also increases their gear and equipment.

I think this spell might be controversial because:

  1. it explicitly allows the caster’s personal items and combative equipment to be enlarged at the same time as the caster, using a +1 magnitude increase. With no mention of how many items.
  2. It does so also without any consideration to how complex or detailed the items are.
  3. The spell makes no mention of casting requirements, and clearly the intent is to change weapons and armour.
  • This sets a precedent for a small magnitude increase to do this in other spells, which is significantly different from what I expected. I’m happy as it’s now canon that this can occur, however I thought it would be harder.
  • This +1 mag for gear adds legitimacy (in my humble opinion) to adding sub effects in Muto transformation spells, and also to making other hybrid Muto spells slightly easier.

    If this wasn’t presented I would have argued that the increase should have been more like +2 and included a note in the spell text to force casting time requisites. Why?

    Well basically these points, however these are a very pessimistic view of spell complexity:

    • It affects multiple items the caster is carrying, perhaps it should have been +2 Group?
    • It affects clothes which are arguably free, but also weapons and arms, which are not.
    • It affects steel, cloth, leather and all manner of other Forms. Perhaps +1-2?

    As a counter in support of the plain +1 increase there is the notion of a small sub-effect in a spell adding a magnitude, and a large spell adding a +2.

    In this case enlarging several worm items as a separate spell would:

    • Still be a Muto spell,
    • Perhaps would be using a higher Base from Terram instead of Corpus,
    • Might be argued as a generic size increasing spell, which we can see in other spells.

    So what is the conclusion? Ars Magica is darn interesting and play what makes you happy, is balanced, and tells a good story.

    Personally I love the fact that this spell exists and it allows the Magus to be closer to mythical. On balance I’m a supporter but I can see the wider issues this introduces.

    The spell when taken by Morat was boosted in effect to increase the size of the caster by a further magnitude, which I renamed to Assume the Stature of the Titans of Rome. So yeah, I took the El Cid spell and boosted it a little more – because at some point it breaks and just before that point is darn interesting.

    Happy role playing folks, enjoy your Ars Magica games.

    Giants vs Vikings

    A worked example of Break The Shield


    I wrote up a short example of how the PeVi spell Break The Shield works against Parma Magica in a forum thread. It’s not my favourite spell in the raw (see grumble below), but it is legitimate in the rules so knowing how to play it out is handy.

    A quick example of Break the Shield (a.k.a BtS, published in Hermetic Projects, p.85) in use by two magi against each other might be:

    Magus Alphar (BtS PeVi15, Pe5, Vi5, Stm3, Pen 0, Parma 2) vs. Magus Betar (BtS PeVi15, Pe10, Vi12, Stm3, Pen 0, Parma 1)

    • Due to the randomness of initiative Alphar casts BtS against his opponent Betar first,
    • Alphar’s BtS PeVi15, CT is 13+roll. He scores CT:20, which is Level 15 with +5 Pen.
    • Betar’s MR is equal to Parma (1*5) + Vim 12 = 17. This means the spell fails to penetrate. There is no need to roll the Level + dice to cancel the spell.
    • Betar returns the same BtS PeVi15 spell, with CT is 25+roll. She scores CT:32, which is Level 15 with +17 Pen
    • Alphar’s MR is equal to Parma (2*5) + Vim 5 = 15. This means that Betar’s spell has penetrated successfully, so now the test of (spell level + roll)/5 vs PM score must be checked.
    • Betar rolls Level 15 +roll, gets a total of 19. This total divided by 5 exceeds is  3.8, which is higher than Alphar’s Parma Magica score of 2, so down goes his Parma Magica.
    • the next round might be ugly for Alphar…

    This demonstrates why low level PeVi spells are handy against supernatural creatures i might stripping, and also why having several Break the Shield Spells might be useful, or investing in mastery and penetration is important for BtS.

    Aside – My grumble about Break the Shield is that it reduces the influence of Parma Magica in the game setting, which in turn was a major justification for the successful formation of the Order of Hermes.

    If BtS was available then why was PM a successful bargaining point. Having BtS in the game also creates an escalation in PM stripping spells as an opening volley. The first magus specialises in stripping parma and then proceeds to decimate the target. Every Magus beyond their mid years should learn the spell and master it using the defense mastery so that they can try to resist it.

    Spell discussion: Sense the Feet that Tread the Earth, 30 Days of Magic

    Now that I look at it “Sense the Feet that Tread the Earth” (InTe30, from Ars core rulebook p.154 – aka StFtTtE) is an interesting spell because it does not require an arcane connection and can grant information that would be otherwise very difficult to determine.

    Within the spell design are three factors worth noting; (a) the InTe Base 4 which “sees” an object and immediately around it, (b) that the object touched can perceive without using requisites, and (c) the StFtTtE spell views a 1 mile radius around the object. It might also be argued that this spell is also not directly scrying, but is certainly indirect scrying – so should have some breadth for compassion in the in-game lore which strongly inhibits Magi scrying on one another.

    The first factor has an interesting range to figure out – the base for InTe4 for earth is 10 cubic paces (Ars p.152), however this spell then adds +3 mags to expand the area of effect 100x times to a 1 mile radius. Logically then a base radius is a 100th of that, equivalent to 5.3 feet – so call it roughly 5 feet radius around the targeted point.

    The second note on removing material requisites is due to the InTe note ” Intellego Terram spell levels are not affected by the material of the thing affected.” That is a very powerful hook to use in creating variations of this style of scrying.

    To further clarify the spell a little, I suggest that StFtTtE cannot detect items which are not walking primarily upon the earth, not moving, and the information sought by the spell must be narrow in nature. i.e. The spell must answer a specific question. Just as “who is walking in the area?” is asked by StFtTtE. This would mean that StFtTtE has no ability to see what people are doing indoors, and also not perceive things that are not moving. Separate spells are needed for different types of information.

    Lastly this highlights that other Forms could have similar effects, like this version for ice and snow written in late 2017, which uses the lower base MuAq3. Here are x5 more variations to be included in the 30 Days of Magic.

    Sense the Vessels that Skim the Seas

    Intellego Aquam 30, R: Touch, D: Concentration, T: Part

    The caster gains abstract knowledge of all objects upon the surface of a body of water for 10 miles around them, allowing them to see objects such as boats, swimmers, or even wreckage in a manner identical to Sense the Feet that Tread the Earth.

    (Base 3, +1 Touch, +1 Concentration, +1 Part, +4 Size)

    Sense the Immediate Malign Steps

    Intellego Terram 20, R: Touch, D: Concentration, T: Part

    The caster gains abstract knowledge of what is moving upon the surface of the earth around them up to approximately 50 feet radius, in a manner identical to Sense the Feet that Tread the Earth.

    (Base 4, +1 Touch, +1 Concentration, +1 Part, +1 Size)

    Sense the Pathway that Twists through the Forest

    Intellego Herbam 35, R: Touch, D: Concentration, T: Part

    The caster gains abstract knowledge of the layout and formations of trees and plants for 10 miles around them, allowing them to see pathways and groves in a manner identical to Sense the Feet that Tread the Earth.

    (Base 4, +1 Touch, +1 Concentration, +1 Part, +4 Size)

    It is also plausible to sense inside the earth or water as readily as what is upon the earth. For that kind of spell the area of effect returns to a more traditional scaling up of volumes, and quickly demonstrates how restricted those spells are at low level.

    Sense the Denizens that Swim the Deep

    Intellego Aquam 25, R: Touch, D: Concentration, T: Part

    The caster gains abstract knowledge of all objects within an area of up to 235,000 cubic feet in size within a body of water (a cube 62 feet to a side), allowing them to see any moving creatures or objects in a manner identical to Sense the Feet that Tread the Earth.

    (Base 3, +1 Touch, +1 Concentration, +1 Part, +3 Size)

    Sense the Hollows that Confound the Earth

    Intellego Terram 35, R: Touch, D: Concentration, T: Part

    The caster gains abstract knowledge of the layout and formations within the earth equal to 100,000 cubic paces (or a cube 46 paces to a side), allowing them to see hollows, tunnels and routes in a manner identical to Sense the Feet that Tread the Earth.

    (Base 4, +1 Touch, +1 Concentration, +1 Part, +4 Size)

    Adding +3 extra magnitudes to these spells makes them more useful for scanning through mountains and oceans, however it makes their spell level very high:

    • InAq25 becomes InAq40 – allowing 235 million feet, or a cube 620 feet per side
    • InTe35 becomes InTe 50 – 10 million cubic yards, or a cube 460 paces per side.

    These spells are part of the free new spells compendium for Ars Magica.

    A tricky MR question for ArM

    I saw a tricky Magic Resistance question for ArM today, and I find it a frustrating demonstration of the MR rules, and a potentially exploitable rule.

    RacconMask wrote – How does this react with Target:Part? If I take (for example) a javelin or spear, and cast a Target: part spell to control the butt of the spear’s haft to attack flawlessly with Rego… does that get magic resistance when the un-controlled tip stabs in? Thinking here of an ‘invisible swordsman’ ReFo spell that only controls the hilt of a weapon.

    Grumble. It is a great idea as it demonstrates again how MR in ArM can be complicated. Truthfully it is no different from enchancing a soldier with a spell to increase their toughness, and insisting that they use normal weapons. Which is to say the players at the table need to understand a simple rule – When a rule is exploitable it can be used by everyone, and the GM has far more resources. Do you really want your enemies to react in the same way?

    As long as the exploit is applies consistently and it feels congruent in the story, let the players exploit. Then hit them with it.

    This is the same for Parma Magica burning spells. They look great on paper, and are exceptionally dangerous, but they also will likley impact the players far more once the NPCs adapt.

    A thought on affecting spells with requisites, a meta-magic question for Ars Magica

    An aside – How do requisites affect which spells can be affected by magic?

    A question raised during the forum discussion asked if a Muto Vim effect could change a spell enough to make it no longer effected by a Perdo Vim form specific effect. e.g. A Sun duration Rego Terram effect is altered to a Rego Aquam effect at cast time – can a Perdo Vim/Terram spell affect it if it has “changed” the form it uses? Further could the same Perdo Vim spell affect only Terram spells, or can it also affect spells with a Terram Requisite?

    I tend toward thinking a spell with a Tech and two Forms can be affected by either Form specific dispel effect. The unraveling affects part of the spells structure and it doesn’t really matter which form it unravels to make the spell loose it’s cohesion. This makes requisites a slight disadvantage, and implies that some part of the original spell is still there to be unraveled.

    But I hold the same concept to other ways of affecting spells it also introduces an advantage to Mu effects affecting the Forms too. i.e. a Muto Vim Terram spell to alter Range up by 1 mag can be applied to any spell using Terram, either as the base form or a requisite. I don’t see adding breadth of application into Vim spells as unbalancing.