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Skip Navigation LinksHigh Fantasy HERO>Content>Campaign Guidelines>Spell Limitations
Magical Effect Limitations
Limited Power Spell Resistance Fatigue Material Components & Physical Objects
Lingering Disruptible Limitations Armor and Magic Restrictions Casting and Armor
Magic System Design is covered here
The limitations and restrictions of a Magic System often define that Magic System more surely than anything else. Following are some suggestions on ways to use Limitations in a consistent fashion to achieve various effects in the HERO System.
Following are some recommendations and guidelines for GM's and Players alike to use when designing Magic Systems and "Spells" or other Magical effects. Options that are in effect in my campaigns are noted, but Players should check with their GM's to determine what options are generally appropriate to their Magic Systems, and any broad restrictions on what Magic can accomplish.
Limited Power
This option is in effect in my campaigns
The HERO System's catch all "isn't listed elsewhere" Limitation sees a lot of use in making unusual Spell effects.
Because the uses for this Limitation are pretty broad, a comprehensive list isnt possible, however there are a few reoccurring Limited Power Limitations that I cover below.
UNDEAD
Some Magical Effects have specific interactions with Undead; some only affect Undead, and some explicitly don not affect Undead for instance.
UNDEAD ONLY
As a Campaign Groundrule, Undead Only is worth a flat -2 Limitation. All Magical Effects presented as examples herein that are Undead Only use the Limitation at this value.
However, obviously in some settings (Ravenloft or similar) or circumstances (such as a campaign centered around an Undead infested ancient city in a setting that otherwise has a fairly normal distribution of Undead or similar) it's much less limiting than a -2.
GM's expecting to run Undead heavy campaigns should consider refactoring this to a -1 Limitation and either back filling affected Magical Effects they want to use with another -1 in Limitations from other sources or increasing the Real Cost of the affected Magical Effects accordingly.
Undead Only: Limited Power (Only vs. Undead, -2)
DOES NOT AFFECT UNDEAD
As a Campaign Groundrule, Does Not Affect Undead is worth a flat -1/4 Limitation, but see "Living Only below"
Undead Exclusion: Limited Power (Not vs. Undead, -1/4)
BODY REQUIRED
Many of the Spells and other Magical Effects presented herein that create Undead are built using the Summon Power. However, the user of such a Magical Effect typically isn't calling a creature from somewhere else to do their bidding; they are creating the Undead creature on the spot. Thus many such Magical Effects require a dead body to work with which is effectively used to "build" the resulting Undead.
Such Spells may take Body Required for a -1/2 Limitation. This is essentially a variation of the "Summoned Being Must Inhabit Locale" option for Summoning and should not be combined with that Limitation.
Need A Body: Limited Power (Body Required, -1/2)
LIVING ONLY
Some fantasy settings feature "creatures" which are not actually alive, most typically Undead, but also Constructs (golems and similar), Magically animated or created entities, and similar. It's up to an individual GM's discretion whether "demonic" or other "outsider" creatures count as Living or not. Also, Magic Items, and even mundane Equipment, terrain features, buildings and the like all obviously qualify as "Not Living".
Magical Effects which Only Affect Living Creatures may take a flat -1/2 Limitation. They have no effect whatsoever on things that are not actually organic and alive.
This Limitation is actually a little more limiting than a -1/2 in some circumstances, but has some benefits as well which counteract this. The primary benefit to this Limitation is that damage Effects that kill living opponents but don't destroy their Equipment or cause collateral damage in the process can be very useful.
You cannot combine this with another Limitation that targets a subset of non living things, such as Not vs. Undead or Not vs. Constructs.
Living Only: Limited Power (Only Affects Living Creatures, -1/4)
ONLY WHILE IN CONTACT WITH THE GROUND
This is a common Limitation for Earth oriented Magical Effects, particularly Geomancy Spells from "Elementalist" types of Magic Systems. If a Magical Effect is only usable while the Magic User is on the ground this Limitation is worth -1/4; if it only works if they are in contact with raw earth, rock, or stone its worth -1/2.
Grounded: Limited Power (Only While In Contact With The Ground, -1/4)
Earthy: Limited Power (Only While In Contact With Raw Earth, Stone, Soil, -1/2)
ONLY WHILE IN SANCTUM
It is possible for a Magic User to use Magical Effects that only work when used in a Base (or Demesnes in the Fantasy parlance) that the Magic User has listed on their Character sheet, defined in points using the Base rules (whether they paid points for the Base(s) or were allowed to purchase the Base(s) with money is immaterial).
This is a pretty significant Limitation, although less so for a Character with a large Demesnes. This Limitation would be ideal for certain Ward type Magical Effects for example. However, it raises some balance and playability issues.
While it does seriously curtail the usefulness of a Magical Effect, reasonably Magic Users simply wont prepare or use such effects other than when in their Demesnes. Thus its not really as limiting in context as it would seem on the surface.
Considering the actual playability of the Limitation, I would recommend -3/4.
Sanctum Sanctorum: Limited Power (Only Functions in/on Base/Demesnes, -3/4)
RITUAL
A new Limited Power sub-system is introduced on page 135 of Fantasy HERO for HERO System 5th Edition called Ritual. This is a really useful and flavorful Limitation which requires multiple Magic Users to work in tandem to activate a Magical Effect.
This Limitation is particularly appropriate for lower Fantasy milieus, and/or Magic Systems that don't grant a lot of individual power to it's users, but is still capable of powerful feats when several practitioners work together.
Any time a Spell needs more than one Magic User to be used, Ritual is the best way to model this. The values for the Ritual Limitation vary based upon the number of Magic Users required; consult Fantasy HERO as needed.
Ritual: Limited Power (Requires Multiple Magic Users, var); consult Fantasy HERO pg 135
WINDOW OF OPPORTUNITY
A new Limited Power sub-system is introduced on page 136 of Fantasy HERO for HERO System 5th Edition called Window of Opportunity. This is a really useful and flavorful Limitation which allows a Spell to only be cast at certain specific times.
This Limitation is particularly appropriate for lower Fantasy milieus, and/or Magic Systems that isn't as strong for day to day use, but can work powerful Magic during certain timeframes.
Any time a Spell can only be cast "Once A Century" or "When The Stars Are In Alignment", or "Once In A Blue Moon", etc, Window of Opportunity is the best way to model this. The values for the Limitation vary based upon the frequency and duration of the Window of Opportunity; consult Fantasy HERO as needed.
WoO: Limited Power (May Only Be Cast At Certain Times, var); consult Fantasy HERO pg 136
REQUIRES A MAGIC SKILL ROLL VS SPELL RESISTANCE
This option is in effect in my campaigns
As indicated under the Spell Design section, one use of Requires a Skill Roll is to represent Spell Resistance. Some creatures and Characters have a Custom Talent called Spell Resistance which provides a Skill Roll only usable for opposed rolls against the Magic Skill Rolls of opposing Magic Users.
If this option is used then many (but not necessarily all) offensive Magical should take this Limitation if their Magic System interacts with Spell Resistance.
If used the "No Active Point Penalty To Skill Roll" option is advisable, resulting in a net -1/4 Limitation when combined with "RSR Skill is subject to Skill vs. Skill contests".
Some of the Magic Systems presented herein do not interact with Spell Resistance; all of the Magic Systems indicate whether they do or do not.
If this Limitation is applied to a Spell or other Magical Effect, the Magic User makes a single Skill Roll with the appropriate Magic Skill Roll when he casts the Spell. Following is a list of possible outcomes.
SPELL RESISTANCE RESOLUTION
Outcome Result
Skill Roll Failed
  • Magical Effect fizzles and has no effect
    • If on Charges a Charge is expended
    • If costs END then END is expended
Skill Roll Succeeds
  • Target(s) with Spell Resistance make Spell Resistance Roll
    • If Spell Resistance Roll made by more than Magic User's Skill Roll, Target not affected.
      • Target(s) win ties
    • If Spell Resistance Roll made by less than Magic User's Skill Roll, Target is affected
An important note is that if this Limitation is applied, then the Magic User must make a successful Magic Skill Roll even if the targets do not have Spell Resistance. If the Magic Skill Roll is failed its important to note that the Spell is still successfully cast, is visible unless normally not visible, and anything else tied to it's casting occurs, it just failed to affect the targets.
The Magic User only makes one Magic Skill Roll; if the Spell has an Area of Effect (AoE), than any and all targets in the AoE that have Spell Resistance compare their individual Spell Resistance Rolls to the Magic User's single Magic Skill Roll. Targets that roll better than the Magic User are not affected, but everyone else in the AoE is affected.
This Limitation is risky, in that it can cause Spells to effectively fizzle which is a major downside for a mere -1/4 (on average) Limitation. However, the percentage chance of this occurring should be relatively small for the average Magic User, and most opponents will lack Spell Resistance. Thus under normal circumstances this Limitation wont affect the Magic User that often so it's a bit of a gamble.
Resisted By Spell Resistance: Requires A Magic Skill vs. Spell Resistance Roll (No Active Point penalty to Skill Roll, RSR Skill is subject to Skill vs. Skill contests -1/4)
SKILL BONUSES ONLY VS SPELL RESISTANCE
To approximate the concept of "Spell Penetration", i.e. the ability to blow through Spell Resistance with Spells or other Magical Effects, a Magic User could buy Skill Levels with their Magic Skills with the Limitation "Only for making Magic Skill vs. Spell Resistance Rolls" for a -2 Limitation if using individual Magic Skills or -1/4 if using the Spellcraft ability. Thus each +3 to a specific Magic Skill Roll would cost 2 points, or 5 points for Spellcraft.
Spell Penetration: +3 with Specific Magic Skill (Evocation, Pyromancy, etc); Only for making Magic Skill vs. Spell Resistance Rolls (-2); 2 points
Spell Penetration - Spellcraft: +3 with Spellcraft; Only for making Magic Skill vs. Spell Resistance Rolls (-1/4); 5 points
SIDE EFFECTS
Side Effects is a very flexible and useful Limitation for making Spells with; any time a Spell has some down side involved with it Side Effects is the most likely appropriate Limitation.
ALWAYS OCCURS
An important detail to remember is that the Side Effects Limitation only occurs if used in conjunction with a Required Skill Roll (RSR) or Activation by default. However, if a Side Effect always occurs, its worth double the value as a Limitation and can be used with Magical Effects that do not have an Activation or RSR Limitation.
FATIGUE
An excellent use of Side Effects is to model the concept of Fatigue. Some Spells or other Magical Effects are very powerful and may tire a Magic User considerably when used. This is primarily a game balance consideration, to reduce the number of times a Magic User might use a particular Magical Effect in a short period of time.
DRAIN BASED
This option is not in effect in my campaigns
Fatigue can be represented by a Drain vs. END or STUN in a Side Effect. Use the Side Effect rules to determine how many points of effect a given level of Side Effect causes, and buy a Drain vs. END or STUN (or both) with that many Active Points. Because it's a Side Effect, a Magic User does not get to apply any Power Defense against this "damage".
A smaller number of dice with a Delayed Return Rate can be used for "long term fatigue", or a larger number of dice at the normal Fade rate for a "short term fatigue" that is shaken off in about a minute or so.
This method does have a few downsides however. Not only does it requires more book keeping, but more significantly the effect often Fades away very rapidly with no long term impact on the Character. In a Fantasy setting with copious Healing magic it can also be effectively erased or minimized by the application of an appropriate Healing Spell.
LONG TERM ENDURANCE LOSS BASED
This option is in effect in my campaigns
Another way to do fatigue with Spellcasting is to use a variant of the Long Term Endurance Loss Optional Rules on page 286 of the HERO System 5th Rules Edition Rulebook combined with Side Effects.
A Character recovers their REC in LTE after 5 hours of rest or once per day otherwise. Thus, this is a very useful mechanic for slowing the casting of powerful Magical Effects, and many of the more powerful long lasting sample Magical Effects provided within this web site use this method.
Even practitioners of Magic Systems that do not use Endurance for Magical Effects (being either 0 END or Charges based) or that use END Reserves are slowed down by LTE loss; eventually they can be reduced to being unable to walk or exert any STR without taking STUN loss.
For simplicities sake, since not all Magic Systems use Endurance, I ignore the normal LTE Accrual by END Spent rules and instead use Side Effects to drive the amount of LTE accrued based upon the number of Active Points in the Magical Effect.
As a Campaign Groundrule, a Spell may take Side Effects at the following levels:
FATIGUE SIDE EFFECT VIA LONG TERM ENDURANCE LOSS
Side Effects Level LTE Loss Limitation Value
Mildly Fatiguing (Minor SE, Always Occurs) AP/10 -1/2
Fatiguing (Major SE, Always Occurs) AP/5 -1
Greatly Fatiguing (Extreme SE, Always Occurs) AP/3 -2
The LTE Loss from this Limitation is in addition to any END Costs a Magical Effect has, and is applied after the initial END cost in the same Phase the Magical Effect is activated. Thus if a Character activated a Magical Effect with 30 Active Points that costs 3 END normally and is also Fatiguing (AP/5 = 6 LTE), the Character would spend 3 END and then takes 6 LTE loss. If the Magical Effect is constant and costs END each Phase then on following Phases the Character spends 3 END but does not take 6 more LTE loss.
EXAMPLE: Unza is a practitioner of a Magic System with some fatiguing Magical Effects that use the LTE Side Effect Option. One of Unza's Magical Effects has 90 Active Points and is "Greatly Fatiguing", indicating that it's use accrues 90/3 = 30 Long Term Endurance loss. Unza only has 35 END, so using this Magical Effect leaves him with 5 END until he can recover from the LTE loss.
Mildly Fatiguing: Side Effects (Minor, Always Occurs): Magic User suffers (AP/10) in LTE loss; -1/2
Fatiguing: Side Effects (Major, Always Occurs): Magic User suffers (AP/5) in LTE loss; -1
Greatly Fatiguing: Side Effects (Extreme, Always Occurs): Magic User suffers (AP/3) in LTE loss; -2
Material Components and Physical Objects
Material Components can help give a Fantasy Magic System greater flavor and verisimilitude, but can also become a major impediment to fun and enjoyment if left to run amok. Following are some considerations pertaining to Material Components
Some Magical Effects might require unusual physical components to function, collectively referred to as Material Components. Some Material Components are relatively mundane, such as charcoal, chalk, candles, string, etc. Others are expensive or exotic or both, such as Gems, rare spices, or raw metal. Still others have mystical or alchemical qualities, such as the clichd Eye Of Newt, Hair of the Dog, etc.
The HERO System provides many ways of representing a Material Component or Physical Object in the context of a Spell, and it can be confusing to the uninitiated as to which is the most appropriate for a given circumstance. Following is coverage of the four most relevant Power Modifiers dealing with a tangible object related to a Power Construct, and recommendations on when to use which.
FOCI
This option is in effect in my campaigns
In the HERO System if you need an item to use a Power construct, you take the FOCI Limitation for that Power construct. If the item is consumed with the use of the Power you may also apply the Expendable option which grants a greater Limitation value depending on how unusual the item is. However, if the item can't actually be taken away from the Character, or is so obtainable as to be easily replaceable then the FOCI Limitation may not be taken.
HOLY SYMBOLS
Divine Magic Users often have a different sort of "Material Component" in the form of a Holy Symbol. Holy Symbols vary by patron entities, but are almost never expendable. They are typically brandished with the casting of each Spell, and a Divinist uses the same Holy Symbol over and over again for various Magical Effects.
I recommend representing Holy Symbols using the FOCI rules; I opt towards OIF (Obvious Inaccessible) since any appropriate Holy Symbol will do (Holy Symbol of Opportunity essentially), but some GM's may prefer OAF (Obvious Accessible). Players should confer with their GM's about this.
USING FOCI
If a particular Magical Effect has Material Components defined via use of the Focus Limitation, then to activate that Magical Effect the Magic User must be able to manipulate the Focus with their own hands, or use it in some fashion. Simply having it on their person in a pouch or backpack is not sufficient unless the Focus is both Inobvious and Inaccessible.
AD&D 2e Conversion
If converting to the HERO System from AD&D and the GM wants to model AD&D as closely as possible, then all converted Spells with listed Material Components in AD&D should take the FOCI Limitation; typically with the Expendable option.
D&D 3e Conversion
If converting to the HERO System from D&D 3rd Edition and the GM wants to model D&D3e as closely as possible, then when converting Spells with Material Components only use FOCI for Material Components with an explicit gold cost. Spells which lack a specific gold cost for their components are assumed to be available in D&D 3e as long as the Magic User has access to their Spell Component Pouch and thus Restrainable is a better Limitation to use in most cases (see below).
RESTRAINABLE
This option is in effect in my campaigns
Rather than taking FOCI, Magical Effects may take a Limitation new to the HERO System in the 5th Edition called Restrainable to indicate that the Power can't be taken away from a Character, but its usage can be curtailed in certain circumstances.
In a Fantasy HERO Context a Character might be allowed to take Restrainable by Removal of Spell Component Pouch (-1/4) if the GM allows it indicating that as long as the Character has access to a Spell Component Pouch they are assumed to have whatever they need to cast individual Spells, but if they can't get to their Pouch for one reason or another then they can't cast Spells that are built with the Restrainable Limitation. This is a more abstracted, less tedious way to handle Material Components, requiring no book keeping.
USING RESTRAINABLE BY SPELL COMPONENT POUCH
If a GM has permitted it and a Magic User has Spells or other Magical Effects which requires a "Spell Component Pouch" to be cast, then that Magic User must be able to access their Spell Component Pouch to use those Spells. Mere proximity is not sufficient. Further this Spell Component Pouch must be displayed somewhere about their person and be reasonably accessible.
D&D 3e Conversion
If converting to the HERO System from D&D 3rd Edition and the GM wants to model D&D3e as closely as possible, then all converted Spells which lack a specific gold cost in their write up should use the Restrainable Limitation instead of FOCI.
PHYSICAL MANIFESTATION
This option is in effect in my campaigns
Some Magical Effects in addition or instead of requiring physical items to be activate create some kind of physical manifestation which can be attacked and destroyed, which will also deactivate the effect. This could be modeled using the FOCI rules, except that FOCI are normally needed for activation of a Power construct, whereas this sort of manifestation is brought into being by activation of a Power construct.
Fortunately, a new Limitation called Physical Manifestation can be found on page 100 in the UNTIL Superpowers Database. Physical Manifestation is a -1/4 Limitation that essentially is treated as a Breakable Focus brought into being by activation of a Power, with a DCV equal to the Base DCV of the originating Character (or logically 0 if left unattended and immobile).
This Limitation is tailor made for making Spells that create a Ward, or a Symbol, or call forth "weapons" which may be attacked directly, and similar effects. I personally favor this new Limitation and encourage it's use where appropriate.
USING PHYSICAL MANIFESTATION
A Physical Manifestation must be accessible, must be attackable, and must be breakable via mundane means. If it is not any one of these things, then it is not really a Physical Manifestation and is just a SFX.
REF: Physical Manifestation, consult Page 100 UNTIL Superpowers Database, Sidebar
LINGERING
This option is in effect in my campaigns
On a related tangent to Physical Manifestation, some attack Spells bring into being an object which may be used to convey an attack repeatedly, such as a Magical Effect that "summons" or "creates" a "weapon" like a Sword. However, most Attack Powers are Instant in nature, and thus don't lend themselves to bringing a reusable "weapon" into effect.
While this could theoretically be represented as a Constant Power construct using the FOCI or Restrainable rules to represent the "weapon", it makes for a relatively clumsy Power construct. Fortunately Fantasy HERO provides an ideal solution in the form of a new Advantage called Lingering detailed on page 257 of the Fantasy HERO Genre Book for HERO System 5th Edition.
Lingering may only be applied to Instant powers and varies in its value based upon how long the Power sticks around on the Time Chart. Without impinging on the IP of HERO Games, suffice to say that a Lingering Instant Power may be used or not used on successive Phases, targeted anew each time, for the duration of the Lingering Advantage. By default the Lingering attack is perceivable for the duration (a variation of Invisible Power Effects may be applied to avoid this), and the SFX of the attack may be defined creatively as usual for the HERO System.
Thus, a "Summon Sword" Spell may be defined as a Lingering Hand Killing Attack, and the SFX of the Spell can be defined as "A sword appears and may be used to strike at opponents".  The "sword" can't be taken away from the Character or attacked directly (unless Physical Manifestation is also taken for the Spell), and really doesn't exist in any meaningful fashion, but has the appearance of being a physical sword.
USING LINGERING
Lingering is a fabulously useful Power Advantage for creating Spells with and I recommend its use, both in and out of conjunction with Physical Manifestation.
However, there have been several clarifying points made by Steve Long regarding the Advantage on the HERO System Rules Questions Forum, available in the HERO System Rules FAQ for Fantasy HERO.
The most significant ruling made thus far as pertains to the content of this website is the relation of Lingering and Charges; Lingering qualifies to unlock the "Continuing" option for Charges, just as if it were a Constant or Continuous Power. This feature of Lingering is used heavily in the Spells provided on this website and should be noted.
Lingering FAQ Entries (as of August 2, 2004)
Q: Regarding the Lingering Advantage on FH 257:
  1. If the spell is in a Multipower and the Multipower is switched to another slot, does the Lingering power remain in effect for its defined duration?
  2. Does a Lingering spell automatically become Persistent?
  3. How does Lingering interact with Charges?
  4. Can characters apply the Uncontrolled Advantage to powers bought with the Lingering Advantage?
A:
  1. As a default, no switching to another Power Framework slot cancels the spell. The GM is free to change that rule for a particular spell or magic system if he sees fit.
  2. No.
  3. If a power has Charges, each use ends after one Phase passes, even if its also a Lingering power. If a character wants to have a Lingering power that has Charges and for which each activation lasts for the specified Lingering duration, he must make them Continuing Charges with a duration equal to the Lingering duration. Since the characters already paying extra for Lingering, (a) he is allowed to apply Continuing Charges to an Instant Power, and (b) you should cap the value of Continuing Charges at -0. The GM can change either of these rules if he prefers otherwise for reasons of campaign balance or the like.
  4. No.
REF: Lingering, consult Page 257 Fantasy HERO for HERO System 5th Edition
Disruptible Limitations
A staple of many fictional and game sources is the idea of "disrupting" a Magic User. It is often one of the primary survival mechanisms for non-Magic Users when facing a Magic User. Suggestions on how to handle this in the HERO System follow.
One of the primary differences between a Spell or other Magical Effect and a Superpower is that most Superpowers are just activated by will alone, whereas Spells usually must be "cast". Casting a Spell or other Magical Effect connotates an accomplishment unto itself, rather than just an assumed non-issue. Many Magical Effects require lengthy preparations, concentration, intricate mystic gestures, and arcane incantations which are delicately arranged just-so to cause the desired result. All of this lends itself to interruption by outside forces, often in the form of an angry opponent wielding a sharpened piece of metal.
The disruptability of an individual Magical Effect is determined by the Limitations placed upon it however. For instance a "Spell" designed as a Power construct without Extra Time, Concentration, Incantations, Gestures, Restrainable, or FOCI may not be disruptable at all, depending upon what other Limitations apply.
Some of the most common Limitations which create opportunities for the activation of Magical Effects to be disrupted are listed below.
EXTRA TIME
The primary single determinant of a Spell's disruptability is Extra Time. A Spell that resolves immediately doesn't leave much time for disruption even if it has taken other Limitations that would make it vulnerable to such.
DISRUPTED BY ATTACKS AND DAMAGE
This option is in effect in my campaigns
For the purposes of Spells it is recommended that the "GM's Option" to have an Extra Time Power be disrupted if the user takes damage or is affected by other attacks before the Extra Time has elapsed described in the 1st col, 4th para on page 186 of the HERO System 5th Edition Rulebook under "Extra Time" be implemented as a Campaign Groundrule.
ONLY TO ACTIVATE
Most Constant/Continuous Spells should apply this modifier to represent a Spell which takes a while to cast initially, but afterwards are not disruptable and work normally.
CONCENTRATION
This option is in effect in my campaigns
If a Magic User must Concentrate to cast a Spell, then the rules provided on page 184 of the HERO System 5th Edition Rulebook indicate that STUN or BODY damage will disrupt the casting the Spell. It is recommended that the GM's Option to allow an EGO roll at -1 per 2 points of STUN or other Damage be implemented as a Campaign Groundrule.
DISTRACTIONS
This option is in effect in my campaigns
Further, it is recommend that any situation which would make it difficult to Concentrate also require occasional Magic Skill Rolls or EGO Rolls (at the GM's discretion). Trying to cast a Spell requiring Concentration while moving at Non Combat Movement speeds in a wagon or while riding, in an environment with strong sensory input (a noisy tavern, a fetid cell, while covered in bugs, etc) and other similar distractions could all impose a Magic Skill or EGO Roll to prevent disruption of a Magical Effect that requires Concentration.
INJURY
This option is not in effect in my campaigns
To increase the grittiness of a campaign, or to depict lower Fantasy, a GM might consider imposing Concentration penalties on injured Magic Users; it's difficult to concentrate when you are in pain, after all. In such a case, a Magic User must make an EGO or Magic Skill Roll to cast a Spell when below normal STUN or BODY. The following modifiers are suggested only; Magic Users could buy Penalty Skill Levels to offset these penalties.
NOTE: This option will seriously curtail combat casting.
Concentration Penalties for Injury
(All penalties are cumulative)
PERCENTAGE OF TOTAL PENALTY
75% STUN or BODY: -1 to Roll
50% STUN or BODY: -2 to Roll
25% STUN or BODY:  -3 to Roll
10% STUN or BODY:  -4 to Roll
At 1 STUN or BODY:  -5 to Roll
INCANTATIONS
This option is in effect in my campaigns
If a Spell requires Incantations, then anything that prevents the Magic User from speaking will disrupt the Spell. Further, as noted on page 192 of the HERO System 5th Rules Edition Rulebook, if the Character takes damage or is affected by any Power construct requiring an Attack roll or ECV Attack Roll, the Power is disrupted or turns off (in the case of Incantations throughout).
DARKNESS VS HEARING
This option is in effect in my campaigns
Per page 192 of the HERO System 5th Rules Edition Rulebook, a Magical Effect with Incantations cannot be cast in a Darkness vs. Hearing Group Area of Effect.
VOICE RANGE
This option is in effect in my campaigns
On page 133 of Fantasy HERO for Hero System 5th Edition an option for Incantations is presented called Voice Range. Normally Incantations have to be obvious "words of power" or similar, but this type of Incantations can be disguised as normal speaking, singing, etc.
However, the target(s) must be able to hear the Incantations, and must be within about 20" of the Magic User if no other strong noise is present. If they can't hear it, whether because there is too much background noise, they are too far, they have been deafened, they block their ears, or otherwise, then they are not affected by the Spell.
Thus such a Spell could be effectively disrupted on a group or individual basis by something making a lot of noise, a person clapping their hands over their ears, someone yelling at the top of their lungs to drown out the Incantations, or similar.
However, as a downside Magic Effect which cause damage would effect the Magic User as well unless they took steps to protect themselves or if the Effect also has Personal Immunity applied to it.
NOTE: This variant of Incantations is used by the Sortilege Magic System detailed on this site.
COMPLEX
This option is in effect in my campaigns
On page 255 of Fantasy HERO for Hero System 5th Edition an option for Incantations is presented called Complex. A Complex Incantation imposes an additional -3 penalty to any Required Skill Roll, or forces an INT Roll at -3 if no Skill Roll is required normally. Failing the appropriate Roll disrupts the Magical Effect.
DEAFENED
This option is in effect in my campaigns
As an extension of the normal Incantation rules, it is suggested that if the Magic User is rendered unable to hear (via a Flash vs. Hearing or a Transform into a Deafened state or something similar) that they suffer difficulties using Spells with Incantations. If the Spell also requires a Skill Roll, it is recommended that the Skill Roll suffer an additional -3 penalty; if the Spell does not require a Skill Roll then it is recommended that the Magic User has to pass an INT Roll at -3 to avoid mangling the Incantations and disrupting the Magical Effect.
GESTURES
This option is in effect in my campaigns
If a Magical Effect requires Gestures, then anything that prevents the Magic User from making obvious Gestures with at least one hand (or if the "Two-Hands" option is taken, all manipulatory limbs) prevents the casting of that Magical Effect. If the Magical Effect requires both Gestures and Extra Time, then stopping the Magic User from Gesturing after he has started activating the Magical Effect but before the Magical Effect has activated will disrupt the Magical Effect.
COMPLEX
This option is in effect in my campaigns
On page 254 of Fantasy HERO for Hero System 5th Edition an option for Gestures is presented called Complex. A Complex Gesture imposes an additional -3 penalty to any Required Skill Roll, or forces a DEX Roll at -3 if no Skill Roll is required normally. Failing the appropriate Roll disrupts the Magical Effect.
ARMOR
This option is in effect in my campaigns
As noted below, Magical Effects with Gestures may force DEX Rolls on Arcane Magic Users wearing Armor, or Encumbered, or both. Several variations on this theme are provided under Casting and Armor below; check with your GM to determine if they are using one or more of the options provided.
FOCI
If a Magical Effect requires a Focus to be cast, if that Focus is taken away from a Magic User before the Magical Effect activates or the Magic User's ability to manipulate the Focus is curtailed (via a grab or an Entangle) before the Magical Effect activates, the Magical Effect is disrupted. Further, if the Focus is broken (using the rules provided on page 189 of the HERO System 5th Rules Edition Rulebook) either during casting or in the case of a non-Expendable Focus on a Constant or Lingering Magical Effect after the Magical Effect has activated, the Magical Effect is disrupted.
RESTRAINABLE
Similar to disrupting a Magical Effect that requires a Focus, if a Magical Effect has the Restrainable Limitation and the Restraining clause occurs before a Magical Effect activates, that Magical Effect is disrupted.
PHYSICAL MANIFESTATION
If a Constant or Lingering Magical Effect has a Physical Manifestation, if the Physical Manifestation is broken the Magical Effect is disrupted.

Armor and Magic Restrictions
In some games it might be appropriate to restrict the wearing of Armor for Magic Users at a GM's discretion. Following are various ways to do so.
Casting and Armor
As attacks are most typically of the Killing variety in Fantasy HERO, Armor takes on a good deal of significance. Since Armor and Magic both are major concerns for play balance, unsurprisingly how they relate to one another is correspondingly also a major concern. If Magic Users can run around in magical plate mail whipping out Magical Effects, non Magic Users will have a correspondingly tougher time of it.
One approach towards handling this is to simply not allow Magic Users with largely offensive Magical Effect lists to wear any Armor at all, and many games have taken this tact over the years. Alternately, you might allow Armor to Magic Users, but with the opportunity for the activation of Magical Effects to be disrupted.
NO ARMOR AT ALL OPTION
This option is not in effect in my campaigns
If the GM has deemed that physical Armor and Magic Use simply don't mix, affected Magic Users have a 100% failure rate of activating Magical Effects while wearing Armor. They may try to activate a Magical Effect if they wish for some reason, but it will always fizzle out, wasting the Effect.
Affected Magic Users may take a Physical Limitation: May Not Activate Magical Effects While Wearing Armor  for -15 points. Alternately a GM may determine that such a Disadvantage is a Campaign Groundrule and not worth any points. Check with your GM first on this subject if playing an Arcane Magic User.
AD&D 2e Conversion
If converting to the HERO System from AD&D 2e and attempting to remain close to the source material, then this restriction should be in place.
ARMOR BUT WITH PENALTIES OPTIONS
Allowing Magic Users to activate Magical Effects while wearing Armor, but with an opportunity cost such as chance of failure, Character Point cost, or a reduction in the Active Points of Magical Effects is a fair alternative to an arbitrary "NO ARMOR" ruling. There are several means by which wearing Armor while using Magical Effects may be penalized; they range from Skill or Characteristic checks, fatigue, Pool-based restrictions, and other options.
These penalties might be used singly or in some combination.
DEX CHECK PENALTIES
This option is in effect in my campaigns for Arcane Magic Users
Under this method Magic Users wearing Armor must make a DEX check whenever they activate a Magical Effect with the Gestures Limitation. This DEX check is penalized for wearing Armor heavier than Light Armor. Similar penalties may be applied for other circumstances as well. These penalties are in addition to the standard penalties for Armor listed in the Weapons and Armament section. The applicable penalties follow.
D&D 3e Conversion
If converting to the HERO System from D&D 3e and trying to remain close to the source material, this version of armored casting restrictions should be used.
Gesture DEX Check Penalties for Wearing Armor
(All penalties are cumulative)
ARMOR TYPE PENALTY
Light -2 to DEX Check (-2 Total, -4 if non-proficient)
Medium -4 to DEX check (-5 Total, -8 if non-proficient)
Heavy -5 to DEX Check (-7 Total, -11 if non-proficient)
Shield -1 to DEX Check (-2 Total, -4 if non-proficient)
Tower Shield -4 to DEX Check (-8 Total, -12 if non-proficient)
Gauntlets -1 to DEX Check
Fully Enclosed Armor -2 to DEX Check
Magic Users may buy Penalty Skill Levels to offset these penalties if they wish.
ARMOR PENALTY SKILL LEVELS TO OFF SET GESTURES
Armor DEX Offset: Penalty Skill Levels: +2 to Offset Gestures DEX Penalty of Armor; Real Cost: 3 points
Shield DEX Offset: Penalty Skill Levels: +1 to Offset Gestures DEX Penalty of Shield; Real Cost: 1.5 points
ENCUMBRANCE BASED VARIANT -- GESTURES ONLY
This option is not in effect in my campaigns
Alternately, it may not be Armor per se which interferes with Magical Effects, but rather Encumbrance. As Armor is heavy and most Magic Users are puny physical specimens, the net effect is that most Magic Users can't activate Magical Effects while in Armor.
Instead of using the above arbitrary penalties, instead base the penalties off of the Encumbrance Table on page 250 of the HERO System 5th Edition Rulebook. Anytime a Magic User is Encumbered, whether from Armor or other sources, they must make a DEX check and suffer the listed DEX Roll Penalties when using Magical Effects with the Gestures Limitation.
REF: ENCUMBRANCE TABLE, Page 250 HERO System 5th Edition Rulebook
ENCUMBRANCE BASED VARIANT -- ALL SPELLS
This option is not in effect in my campaigns
Instead of using the above arbitrary penalties, instead base the penalties off of the Encumbrance Table on page 250 of the HERO System 5th Edition Rulebook. Anytime a Magic User is Encumbered, whether from Armor or other sources, they must make a DEX check and suffer the listed DEX Roll Penalties when using all Magical Effects, whether they have the Gestures Limitation or not.
REF: ENCUMBRANCE TABLE, Page 250 HERO System 5th Edition Rulebook
FATIGUE PENALTIES
This option is not in effect in my campaigns
Under this method Arcane Magic Users wearing Armor grow tired quickly when using Magical Effects. There are various levels that this might be set at, and may interact with one or more Power Limitations taken on Spells.
ENDURANCE LOSS
With this variant using a Magical Effect while wearing Armor is tiresome in much the same fashion that swinging a sword is. The Magic User spends Endurance equal to the Active Point Cost of the Spell divided by 10 (AP/10) just as they would for any Endurance costing Power.
If a Magical Effect already costs END, this END cost is in addition to any other END cost but must be paid for with personal END, not from an END Reserve.
LONG TERM ENDURANCE LOSS
With this variant using a Magical Effect while wearing Armor saps the strength of the Magic User and takes quite a while to recover from. The Magic User suffers Long Term Endurance (LTE) loss equal to the Active Points of the Power divided by 10.
If a Magical Effect already costs Long Term Endurance for some reason, such as a Side Effect, this LTE loss is in addition to any other LTE loss.
MAGIC SKILL ROLLS AND PENALTIES
This option is not in effect in my campaigns
Under this method Arcane Magic Users using Magical Effects while in Armor must succeed at an appropriate Magic Skill roll. If the Magic Users system of magic already requires such rolls to activate Magical Effects, a couple of ways of dealing with that are covered as well.
NO MAGIC SKILL NORMALLY REQUIRED
If this option is used with a Magic System that does not require Skill rolls be made to activate Magical Effects, then for no extra Limitation value wearing Armor forces a Skill Roll with either a suitable Magic Skill or failing that a Characteristic Roll (typically INT or EGO), and suffers the standard -1 per 10 Active Points penalty.
MAGIC SKILL NORMALLY REQUIRED, DOUBLE JEOPARDY
If a Magical Effect already requires a Skill Roll to activate, one way to handle Armored casting is to have the Magic User make two such skill rolls; one to activate the effect normally and another to see if the effect fizzles due to the Armor (conceptually either because Armor intrinsically disrupts Magic or because the Magic User's freedom of movement is curtailed, depending on the GM's preference).
MAGIC SKILL NORMALLY REQUIRED, GREATER PENALTY
An alternative for systems with a Required Skill Roll is to just increase the existing penalty to the roll (if any). I would recommend the following penalties in such a case..
Magic Skill Penalties for Wearing Armor
(All penalties are cumulative)
ARMOR TYPE PENALTY
Light -1 to Magic Skill Check
Medium -2 to Magic Skill Check
Heavy -3 to Magic Skill Check
Shield -1 to Magic Skill Check
Tower Shield -4 to Magic Skill Check
Gauntlets -1 to Magic Skill Check
Fully Enclosed -2 to Magic Skill Check
POOL AVAILABILITY RESTRICTION
This option is not in effect in my campaigns
Another way to restrict Armored Magical Effects use is to permit it only for Magical Effects that are "casual" for an individual Magic User, granting more powerful Magic Users greater capability to wear Armor. This has the benefit of allowing something to Characters that are likely so powerful it's a moot point regardless. The Magic User that can cast a 100+ Active Point defense Magical Effect isn't likely to sludge along in Plate Mail after all.
Under this type of variant, Magical Effects with a fraction of the Magic User's normal Active Point limit are castable in a given type of Armor, as depicted below. All penalties are cumulative.
Active Point Limits While Wearing Armor
(All penalties are cumulative)
ARMOR TYPE AP PENALTY
Light -25%
Medium -50%
Heavy -75%
Shield -15%
Tower Shield  -50%
Gauntlets -15%
Fully Enclosed Armor -30%
EXAMPLE: Findros the Magnificent has a 120 Pool Magic VPP. While wearing Heavy Armor he can cast Spells of 30 Active Points or Less (25 % of 120), but may not cast Spells of 31 or more Active Points; if he also carried a Shield, he would only have -75% + -15% = -90% = 12 Active Points available -- not enough to cast much of anything with. Conversely if wearing Light Armor he would have 90 Active Points available, and with a Shield 78 Active Points.
TALENT BASED RESTRICTION
This option is not in effect in my campaigns
Yet another way to restrict Armored Magical Effect use is to permit it, but only for those who have purchased a costly Talent for the privilege. This has the advantage of allowing certain Character concepts, but with an "overhead cost", while at the same time acting to generally restrict Armored juggernauts whipping out Fireballs and Lightning Bolts.
The cost of such a Talent might need some adjustments depending on the overall point level of a given campaign, but the following should work for most circumstances.
Armored Casting (Custom Talent)
This Talent allows a Character to activate Magical Effects while wearing Armor. The Character must also be proficient with the applicable Armor.
Armored Casting: 10 Points to activate Magical Effects while in Light Armor and/or with a Shield, 15 Points while in Medium Armor, or 20 Points while in Heavy Armor. +5 Points to use a Tower Shield while casting Spells whether in Armor or not.