Magic Rules

How it Works

Spontaneous Magic

  1. Determine what the spell is trying to do.
  2. Determine the Form and Technique being used to cast the spell. This may be obvious from what the spell is trying to do, or the player may need to explain how he/she is using the Form and Technique to generate the effect.
  3. Determine the power level of the spell.
  4. The character expends one mental stress.
  5. The player rolls the dice and adds the number of successes to the caster’s Form + Technique. If this total is equal to or higher than the spells power, then the spell is cast successfully. If the total is lower than the spell’s power, then the caster may opt to take the difference between the two as mental stress in order to cast the spell successfully. This may end in consequences or even being taken out. If the total of the roll + Technique + Form is lower than the spell’s power and the caster chooses not to take the mental stress, then the spell is uncontrolled and will have an effect on the scene and those in it as determined by the GM.

Formulaic Spells

  1. Declare a formulaic spell you want to cast.
  2. Assume you have rolled zero successes to cast the spell.
  3. Look at the power level of the spell. If it is equal to or less than the character’s score in the Form + Technique of the spell, then the caster has cast the spell. If this power is more, the caster must take additional mental stress to make up the difference or let the spell fail.

Casting a Formulaic spell from a text copy of the spell is possible, providing a +2 to casting the spell if you already know the spell, however you’ll have to study the text before casting the spell. Characters may cast spells they do not know from a text. Again the character will have to study the text of the spell but they will not receive any bonus to the casting and they may have an extra Botch aspect (explained below).

Some Formulaic spells will have a range, duration or targets with two values separated by a “/”. These formulaic spells may have these attributes modified by expending raw vis. See “Using Raw Vis” below.


There are three different ways to cast a spell under Bonisagus’s Magic Theory. The way a caster casts it is a product of considering his knowledge of the effect and the time he has to produce it.
Spontaneous:Spells cast in this manner are created by the caster in the moment. They follow general guidelines and precautions but are often less efficient and refined.
Formulaic: Formulaic spells are spells with well understood procedures that give a specific effect. These spells are very strict in the result they produce.
Rituals: Rituals are formulaic spells however their casting is more complex and involved. Through these additional complexities rituals are able to overcome some weaknesses of spontaneous and formulaic spells.
Spontaneous and Formulaic magic are restricted in that:

  • They cannot affect an area larger than you can see (though the effects may move out of your sight and control once a spell is cast).
  • Their duration cannot be longer than one month.
  • They cannot be used to perceive anything in the past or future.

Ritual Spells

  1. Determine the ritual spell you want to cast.
  2. The character spends 15 minutes (story time not real time) per power level meditating on the spell.
  3. The character must then spend an amount of vis of a type or types in the spell equal to the spells level.
  4. Expend one mental stress.
  5. Look at the power level of the ritual. If the caster’s score in the Form + Technique of the ritual is equal to or more than the power level, the caster has cast the spell. Otherwise the caster may expend additional mental stress, gaining power in the ritual on a one for one basis. For each stress expended in this manner, the ritual takes an additional scene (approx. 2 min) to cast. The caster may also be able to draw energy from other sources, (other magi participating in the ritual are able to provide power on a one power for one mental stress basis also -there is a reason the most powerful magus generally leads a ritual, draining magical items or aura is an option that may destroy the resource in the process, blood sacrifices are possible though the Order generally frowns on such practices).
  6. When the magus has enough power invested in the spell to cast it; the spell is cast. If the magus loses consciousness or stops investing the spell with energy the spell fails. Targetting rolls are rarely required for casting ritual spells.

Spell Targeting & Penetration

Magic is a hard thing to control. The more powerful a spell is, the harder it is to get it to go where you want it to. During the casting roll for a spell, any successes above what is needed to match the power of the spell can be used as either targeting or penetration.

The caster can declare any number of the overage from the casting roll for targeting or penetration. Successes declared for targeting are added to the caster’s Finesse to determine the target’s difficulty for dodging the spell effect. Overage declared for penetration is subtracted from the target’s magical defenses to lower their chances of resisting the spell.

Not all spells need to be targeted and not all spells can be resisted. The distinction is subtle but basically breaks down according to what the spell is trying to do. If the spell is acting through a medium to affect the target (creating a ribbon of fire that streaks toward the target, e.g.), then is needs a targeting roll. If it is affecting the target directly (opening pustular sores, e.g.), then it can only be resisted. Lastly, a spell can affect the environment around the target in which case there may be a roll that allows the target to escape the effect of the spell but beyond that there is little hope.

Spells cast on an area don’t require targeting.

Spell Botches

Sometimes a caster casts a spell but the spell doesn’t come off quite right, the caster maybe missed a syllable or flicked his wrist a bit hard. This can lead to the spell having unexpected effects and/or targets. This is called a Botch.

The game handles Botches by making them aspects. Every spell has an aspect called Botch that can only be compelled. What it means to Botch a spell is left to the GM to determine though some spell formulas may specify how a spell Botches when cast.

Spell Mastery

After reaching a Milestone, skill points may be used to Master formulaic and ritual spells. For each point put into Mastering a spell the character gains a point toward Mastery of that spell. When a character has a number of points toward Mastery of a spell equal to the spells power the character has mastered the spell.

When casting a Mastered spell, the Magus assumes a roll of +2 instead of a +0.

Using Raw Vis

Raw vis can be used to strengthen or modify spontaneous or formulaic spells upon casting them.
To do so you will have to declare the amount of raw vis you are spending before casting the spell.

Vis acts as raw power being fed into the spell. Add +1 to your roll for each pawn of vis spent casting a spell.

Some formulaic spells are created with built in options for extending characteristics of the spell through vis expenditures. An amount of Vis equal to the power of the spell of either the Form or Technique of the spell must be used to upgrade the spell in such a way. If the caster wishes to use more than one such option on a spell, each upgrade must be paid for separately.

Magi are limited in the amount of vis they can use in a single spell. A magus may only spend an amount of vis equal to his/her score in the Art associated with that type of vis.

The Arts – Forms and Techniques


ANIMAL-Animal concerns animals of all kinds, from the fish of the sea to the birds of the air. Animal spells cannot affect people, for they have souls whereas animals do not. Pronounced ‘ah-nee-MAHL.’
AQUAM-Aquam concerns all manner of liquids. Through this Art, one gains access to the might of a roaring flood and the gentleness of a clear pool. Pronounced ‘AH-kwahm.’
AURAM-Auram is the Art of air, wind, and weather. True flight is only possible through this Art. Pronounced ‘OW-rahm.’
CORPUS-Corpus is the Art of humans and humanlike bodies. It governs the intricate interactions that occur in those bodies with souls, as well as those that once had souls. Pronounced ‘COR-poos.’
HERBAM-This Form concerns plants and trees. This includes plant matter of all types, including that which is no longer alive—like dead wood and linens. Pronounced ‘HARE-bahm.’
IGNEM-This Form concerns fire, heat, and light. Fire is the most lifelike of the four elements: it moves, it devours, and it grows. Also, just as a living thing, it can be killed by the other three elements—smothered by earth, quenched by water, or blown apart by wind. Fire’s position midway between inert matter and living being gives it the advantages of both. Pronounced ‘IG-nem.’
IMAGINEM-This Form concerns illusions and phantasms. It affects only the senses and can never affect matter. Masters of this Art have learned to separate the impressions a thing leaves on the senses from the thing itself, and many of them likewise become separated from what those around them see as reality. Pronounced ‘ih-MAH-gihnem
MENTAM-This Form concerns minds, thoughts, and spirits. It comes as close as magic can to affecting souls. Through this Art, magi manipulate what they call the body of the soul: memories, thoughts, and emotions. They can also affect the “bodies” of incorporeal beings, such as ghosts, as these are maintained in the physical world directly by a spirit’s will. Pronounced ‘MEN-tem.’
TERRAM-This Form concerns solids, especially earth and stone. Indeed, Terram affects the very foundation of the world. Although Terram magic is mighty, the earth proves resistant to manipulation. Just as stone is heavy and hard to lift, it is inert and hard to change, even through magic. Pronounced ‘TARE-rahm.’
VIM-This Form concerns raw magical power. All the Arts rely on the raw energy and potential of magic, but this Art refines the use of magic itself, allowing magi to assume even greater control of their spells. Vim also affects demons, which are innately magical creatures. Dealing with demons,however, is dangerous because of the risk of corruption and because it is against the code of the Order of Hermes. Pronounced ‘WEEM.’


CREO-This Art allows you to produce objects from nothing. It turns dreams into reality. When using a Creo spell, you enter a momentary state of transcendent meditation and contact the realm of Forms, in which all the objects that ever were and ever could be exist as perfect ideas. Your magic finds the proper Form and impresses it on the real world, creating an expression of it. Objects created this way are closer to the world of Forms than are normal objects, so they are always perfect and flawless. You can also use the Art of Creo to perfect things that have deteriorated from their ideal nature, such as to heal a broken arm or to mend a broken vase. Pronounced ‘CRAY-oh.’
INTELLIGO-Intéllego is the Art of perception. All things in the world are connected to each other, and Intéllego allows magi the ability to see, read, and learn from these connections. Pronounced ‘in-TEL-lego.’
MUTO-This is the Art of transformation and transmutation. Through this Art, magi can direct and control the essential mechanisms of change itself. A transformation is easiest when there is a strong connection between the original object and that resulting from the transformation: for example, it is relatively easy to turn a leaf into an apple. However, turning a leaf (living, flexible, and vegetable) into a sword (inert, unyielding, and mineral) is quite difficult. Pronounced ‘MOO-toe.’
PERDO-The one trait held in common by all objects and creatures in the temporal world is that some day, inevitably, they will cease to exist. The magus who understands the Art of Perdo knows this, and uses magic to control the universal process whereby things are destroyed. Aging, disease, decay, and dissolution are all properties inherent to objects and living things and can be drawn out through this Art. Pronounced ‘PARE-doe.’
REGO-The Art of Rego allows a magus to regulate matter or compel the actions of living things. One kind of Rego spell might lift someone into the air, and another might make a person act a certain way. Pronounced ‘RAY-go.’]

Limits of Magic

Magic, though a very powerful force, is not omnipotent. There are certain laws it must conform to and certain limits that it can never exceed. These limits to Hermetic magic are drawn from the medieval paradigm of post-Aristotelian, pre-Copernican physics and cosmology, and are described below.

The Limit of the Lunar Sphere

Hermetic magic cannot affect the lunar sphere, nor anything above it.

The Limit of Divinity

Hermetic magic cannot overcome the power of the Highest Divinity or the deceptions of infernal powers. Thus it cannot affect the outcome of a miracle, manipulate the mind or body of someone buried in piety by the Church, alter True Faith, detect the presence of the deceptions or illusions of a demon, nor determine the purposes behind those deceptions or illusions.

The Limit of the Soul

Hermetic magic cannot affect an immortal soul, and so may not create true human life nor restore the dead to life.

The Limit of Essential Nature

Hermetic magic cannot alter or determine something’s essential nature. Thus it cannot halt or reverse natural aging, affect the heart-shape of a Bjornaer magus, nor create, destroy, or alter any supernatural aura.

The Limit of Creation

Hermetic magic is incapable of creating anything permanently without raw vis, which includes curing permanently without raw vis.

The Limit of Time

Hermetic magic is incapable of altering the passage of time. It cannot affect anything in the past, and can only affect the future by making changes in the present.

The Limit of Energy

Hermetic magic cannot restore one’s physical energy so that one can cast more spells and cannot remove consequences taken for casting spells.

The Limit of Arcane Connections

Hermetic magic cannot affect an unseen target without an Arcane Connection.

Always keep in mind that the “laws” of post-Aristotelian, pre-Copernican physics are not rules, they are facts. Magic cannot contradict them. You can lift an object in the air, defying gravity, but you cannot eliminate gravity itself; you can see into the past, but you cannot change it.

The boundaries of Hermetic magic are well known to the Order, but that doesn’t stop magi from challenging them. Indeed, many magi spend countless years searching in vain for a way to transcend these limits. Certainly, any magus who actually succeeds in doing so will become famous, perhaps as famous as the Order’s very founders.

Determining Spell Power Level

These are general guidelines for determining the power of a spell. A spell may not have a level lower than 1.

Damage: If the spell is meant to deal damage, then it will normally cause one damage per level employed to that end. So a spell that deals 2 physical stress automatically has a power of at least 2.
Block: Spells can block actions and prevent damage, again on a one block strength for one spell level exchange. So a block strength of 2 is at least a level 2 spell, but if the block is broken it disappears no matter the duration of the spell. A block can be declared as an armor effect by halving the block strength. In this form the spell will prevent damage for its duration and won’t disappear if any damage gets through.
Manuever: Some spells create circumstances that are advantageous to the caster or a disadvantage for his adversaries. These spells create or remove aspects from scenes and individuals. These spells normally start at a level of 3.
Healing: The level of a healing spell is based on the consequence the spell is affecting plus 4 (3, because all healing spells start at a Sun duration, plus 1, because the first thing the spell must do is stabilize the wound). So, healing a moderate wound is a level 8 spell ( most healing spells adjust the range down to touch so the spell would be level 4, see below). This makes the consequence last as if it were a consequence of the level below it, in the case of a minor consequence it removes it. A spell may effect a number of consequences at a time, but each consequence takes an exchange to effect in the order of the minor to the extreme and each consequence effects the spell level separately. Also a spell may drop the healing time of a consequence multiple levels but each drop in level takes an exchange to take effect and increases the level of the spell by the penalty of the consequence it is healing as. For example, to heal a moderate and a mild consequence fully the spell would be level 12 (4 to start + 2 for the mild + 4 for the moderate + 2 to remove the mild healing time from the moderate) and would take three total exchanges to bring the target to no consequences (the exchange the spell was cast in, the mild consequence would be removed, the next exchange the moderate would have the healing time of a mild, the third exchange the moderate would be removed). Note that consequences in the process of healing still occupy the slot they are in and still may be tagged, invoked or compelled until they are removed. Healing spells require an amount of vis equal to their level in order to make the effect Instant (see below, Duration), otherwise the effect lasts until the next sunrise/sunset and then the consequence returns. If a consequence returns and a consequence is in the slot the returning consequence once occupied, then the returning consequence takes the next available slot down and becomes a consequence of that severity. If no lower slots are available the character will be considered taken out. Extreme consequences are, of course, a special case in that the aspect changed, by taking an extreme consequence, is not changed back for healing the consequence, though it may be modified so that it makes logical sense within the story.

Ranges(from low to high)Durations(from low to high)Targets(from low to high)

RangePower Mod.
Arcane Connection+1

DurationPower Mod.

Targets/AreaPower Mod.

Duration: Most spells tend to be momentary. There are effects that need longer durations in order to work. Increasing the duration of a spell increases its power. The power of the spell increases by 1 for the first step from momentary to concentration and by 2 to get from concentration to sun. Then it increase by 3 for each additional step up the duration scale.
Range: The range of a spell is generally sight. Going below this range will make the spell easier to cast, going above it is generally not possible without an arcane connection. Reducing the range reduces the power level of the spell by 1 per step down the range chart.
Area: Normally a spell targets an individual, but magic can be flashier than that. A caster can increase the area a spell affects by increasing the power of the spell. Each step up the Targets scale increases the power of the spell 2 plus the cost of the previous step (So the first step up is 2. The next step up is 4. The next is 6.). Each step must be incorporated to move up to the next step.


Personal The effect of the spell is centered on the casting magus. The amount affected depends on the effect of the spell.
Touch/Eye Touch: The magus or anything he touches, whether a person or thing. Eye: The magus may target any person or creature that he has established eye contact with. (Touch and Eye are the same “level” of range.)
Reach Anything that the magus could touch (but is not necessarily touching) without moving substantially.
Near Anything within the same zone as the magus.
Far Anything in two or three adjacent zones of the caster’s zone.
Sight Anything that the magus can see. If the magus is standing on the highest point for miles, this range can be immense.
Arcane Connection Anything that the magus has an arcane connection to. Distance is immaterial unless the GM chooses to impose some limit. Note that while Arcane Connection is a range, it is different from a physical item that is an arcane connection. This distinction is important, because some spells require that the caster have an arcane connection, but the spell must be cast as some range other than Arcane Connection.


Momentary The spell lasts but a moment and then dissipates. Any effect that it has remains, however. This is the normal duration for combat spells.
Concentration/Diameter Concentration: The spell lasts as long as the magus concentrates. Diameter: The spell lasts for the time that the sun takes to move its diameter in the sky—almost exactly two minutes. (Diameter and Concentration are the same “level” of duration.)
Sun The spell lasts until the sun next rises or sets
Moon/Ring Ring: The spell lasts until the target of the spell moves outside a ring drawn at the time of casting, or until the ring is physically broken. Moon: The spell lasts until both the new and full moon have been in the sky. (Moon and Ring are the same “level” of duration.)
Season The spell lasts until the next solstice or equinox after its casting.
Year The spell lasts until the fourth equinox or solstice after its casting.
Perm/Inst Permanent: The spell lasts forever, but remains forever magical. Thus, it could be dispelled at some point in the future. This duration is only available for spells which have magical effects: natural effects are Instant duration instead. Instant: The spell effect persists forever as a mundane thing. It cannot be magically dispelled, although it can be destroyed by any method which would destroy the mundane thing that it is. This duration is only available for spells which have natural effects. Note also that this duration cannot be attained for magical creation or healing without the use of raw vis. (Permanent and Instant are the same “level” of effect.)


Small Affects a small item, something a person of average strength could comfortably hold or carry with both hands.
Individual The spell can affect a single discrete thing, such as one person or one object. A huge boulder is a discrete object, a mountain is not (because it is joined to the ground).
Group/Room Group: The spell can affect a small group of people or things. There should be no more than about a dozen things, and they must be an obvious group. Three grogs huddled together or a ring of standing stones are a group: six people out of a crowd are usually not. Room: The spell affects a chamber and everyone or thing within it. This room can be very large (the nave of a cathedral, for instance, or a natural cave), but it must be enclosed and have definite boundaries. A courtyard would often count, a valley would not. (Group and Room are the same “level” of effect.)
Circle/Structure Circle: The spell affects everything within a ring drawn by the magus at the time of casting, and ends if the circle is broken, irrespective of the nominal duration of the spell. Structure: The spell affects a single structure and everything within it. The structure can range in size from a hut to a castle, but it must be a single, linked edifice. As a rule of thumb, if it is all covered by one roof, it is one structure, but storyguide discretion applies. (Circle and Structure are the same “level” of effect.)
Boundary The spell affects everything within a well-defined natural or man-made boundary. This could be the wall of a city, the edge of a village, the shores of a lake, the edge of a forest, or the bottom of a mountain. Since the ocean is not obviously bounded, it cannot be affected in this way. The magus must be able to see most of the bounded area unless the spell is being cast at Arcane Connection range.
Sight The spell affects everything within sight of the caster.

Spell Modifiers

Laws of Magic:

The Law of Contagion: (Once together, always together.)

Having a piece of the subject you are trying to affect makes it easier to effect the subject. Sometimes this bond can be strengthened through expenditure of Vis. Generally having an object that is a piece of or an object strongly associated with the subject of the spell acts as an aspect on the subject that the caster can freely invoke only on that subject. Once the aspect in invoked the object loses this connection.

The Law of Sympathy: (That which looks alike, is alike.)

Magi often use this law by creating or finding a replica ( usually in miniature) of the subject of the spell they intend to cast. The replica is then used to visualize the effect of the spell by making the replica change to the state the spell is trying to bring about in the subject. For example, if a magus were trying to put out a house fire, he might build a small fire and then as the he finishes casting his spell he would extinguish the small fire and the act of doing so would strengthen his spell. Generally this gives the caster an aspect on the subject that may be invoked for free.

As is, these laws are quite powerful; however preparation can increase their power considerably. To do so, the caster must first have an open enchanted item slot. The caster then opens the item to enchantment. The caster spends a season action to add a number of aspects that the item can be used to call on the target. This number of aspects is limited in two ways; the number of aspects may not be greater than three, the item may only take one aspect for every two Vis used to open it to enchantment. The caster then makes a Magic Theory roll at a difficulty equal to two times the number of aspects placed in the item. If this roll is successful, the caster then spends a number of Vis equal to two times the number of aspects applied to the item in order to close the process. Each of these aspects may be invoked for free by the caster. The caster may choose to do them one at a time or all together; however once an aspect on the item is invoked it is erased from the item. Once all aspects on the item are used the item no longer holds any connection to the subject. Objects used in this way can not be used as arcane connections.

Voice and Gestures:

Spells are normally cast through the use of clear, forceful voice and precise yet obvious gestures. This isn’t always desirable or even possible. A magus can cast a spell using subtle gestures by increasing the difficulty of casting the spell by one shift. He can cast the same spell by speaking softly by increasing the difficulty of casting the spell by one shift. A magus may cast a spell without speaking or gesturing by increasing the difficulty of casting the spell by 2 shifts each. Exaggerated gestures and a loud booming voice each give a bonus to casting the spell by lowering the difficulty by 1 shift each.

Spell Requisites:

Sometimes the effect that a spell is trying to achieve crosses the boundries set by the Forms that are being applied. For instance, a caster may wish to have air above a target turn to rock and fall onto a target doing damage. This is a Muto Auram effect but rock (Terram) is a by product of the spell. This spell has a requisite, Terram in order to achieve the effect. A requisite simply means that you compare the level of the primary Form or Technique with the requisite Form or Technique. If the requisite Form or Technique is lower than the primary Form or Technique use the lower of the two to determine your spell casting total.

Magic Defense

There are a number of ways to protect ones self from the effects of harmful magic. These defenses come in two flavors, natural defense and magical defense. Many spells can be avoided or reduced through normal means. Spells that create an attacking medium can normally be dodged. A targets own faculties may be sufficient enough to over come the effects of a Mentam spell. On occasion though, these defenses aren’t enough. Thus, Magi have created ways of protecting themselves.

Parma Magica:

The use of the Parma Magica is unique to magi of the Order of Hermes, but it is not a genuine spell. Rather, it is a ritual that focuses magical energies into a shield around you and others you designate it to protect. It takes about a minute to perform this ritual, and all those who are to be protected must be present.
When protecting more than one person, the magus’s parma magica score is split between the number of targets being protected. When one of these protected targets becomes the subject of a spell the target rolls their defense as normal with a bonus equal to the parma magica score bestowed on them.

Force of Will:

Sometimes when magic is turned against a magus, it can be benificial for the magus to hold his ground instead of jumping around trying to dodge gouts of flame. When this is the case, a magus might choose to fight magic with magic. When confronted by hostile magic, the magus may choose to roll the primary Form of the spell in place of a natural defense roll. The magus must have a score in the Form of the spell. The magus does get his parma magica bonus to this roll.


Magic Rules

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