Prism Appendix C RDI

Art copyright  Clyde Caldwell, used by permissionC.1 What is RDI?

The RDI System of Magic is an alternative to the systems presented in the previous two appendices.  It leans heavily on Spell Law™ as a reference, so you should be familiar with that system (and possibly with the adaptations that make it usable with Prism in Appendix A, though that's not as necessary) before you attempt to use RDI.  This system requires a GM to be very comfortable with magic, and is easily abused; play balance is left almost entirely to the GM in favor of versatility.

There's one common element behind Spell Law™, GURPS Magic™, and most other roleplaying game magic systems: they are effect-based rather than cause-based. This means that spells are described in terms of their effects, in a mechanistic way, and therefore, spells can be listed exhaustively.  Except for some special rules for inventing new spells, usually involving much research, these systems require spellcasters to use pre-defined spells that may not exactly suit their needs.  This is a perfectly reasonable approach.  After all, who's to say magic doesn't work that way?  Magic is especially hard to reality-test.

However, if you read fantasy adventure fiction, you'll find that each world tends to have its own view of the rules of magic, and the best of them have wide differences.  As an example, compare the magic systems of The Earthsea Trilogy by Ursula K. LeGuin, The Belgariad by David Eddings, The Chronicles of Thomas Covenant by Stephen R. Donaldson, and The Riftwar Saga by Raymond E. Feist.  None is quite like the typical roleplaying game system (The Riftwar Saga includes a Spell Law™-like system as one possible method of magic, but the main wizard character does not use it) and each is very different from the others.  It seems that roleplaying games could benefit from having a variety of magic systems to choose from.  This is why I have presented three different ones in the appendices.  However, while many of the details of Spell Law™ and GURPS Magic™ are different, the operative principles are quite similar.  RDI is an attempt to get away from that.  Note that RDI is not intended as a "better" system, in any sense.  It is actually a great deal harder to run (I speak from experience here) and it can be easy to lose hold on a campaign using RDI if you're not careful.  It is simply another choice you can try out in some campaign.

What makes RDI so different?  Well, the main difference is that the RDI system does not use a list of spells.  Instead, spellcasters invent their own spells each time they cast them, and their only limits are how difficult the spell is and how much skill they have.  Magical abilities are now simply forces or tools to be manipulated by the casters to do whatever they wish to do.

To maintain flexibility, many decisions about the way magic works are left for the GM.  For example, there are no "realms" of magic.  If you wanted to use realms, it would be simply a matter of dividing the 18 spell skills into realms and then requiring each character to choose a realm and stick to the skills in it.  The sub-aptitudes described in section A.2.3 might be used as well if desired.  It should be easy for the GM to make these types of adjustments.  Here's a few questions the GM can use as a springboard to find ideas with which to make magic unique in their game world:

C.2 Character Creation

C.2.1 Stats

As with all magic systems, Will represents the character's magical strength, and Resistance her magical resistance.  A good Will is very valuable in the RDI system and GMs may even require it.

C.2.2 Abilities and Weaknesses

Note that the Spell/Psion Enhancement ability does not apply.  In the RDI system you specify the range, duration, and area of effect of a spell when casting it, so this ability would be meaningless.  Instead, just specify a larger duration or whatever; the spell ends up being harder, of course.  Save the character points you might have spent on the ability and use them to improve your MIND aptitude, and then develop the skills higher, and you end up getting the same benefit.

Ask the GM before taking the Archmage ability.  It probably won't be allowed.  (A 1 AV in MIND should be more than enough for anyone in RDI.)

C.2.3 Aptitudes

As you might expect, the MIND aptitude is crucial here.  However, you can really get some use out of a moderately poor MIND AV if you don't intend to make magic your only talent.  Unless your GM wants to restrict it, you can always develop a tiny bit of skill sufficient for a few spells with an AV of 5 or 6 and round out a character.  In RDI this can really be useful.  (In most other systems you can't afford to get skill enough to do more than one or two spells, but in RDI you can do any simple spell in a broad category you want with just the one skill.)

After you've bought your aptitudes you also have to decide which of the various spellcasting categories you prefer.  You will assign Diff Mods to the 18 spell skills.  (There are a few supplementary skills in there as well, so don't get them mixed up.  The spell skills are all marked with a µ symbol.)  Diff mods must range from -3 to +3 (unless the GM allows otherwise) and must add up to 0.  You must be ready to explain a reason for any Diff Mod of +2 or worse (so that you're not just taking them for points).  It is best to choose a theme and assign points based on it.  For instance, a wizard might specialize in elemental magic, nature and life magic, spiritual and non-physical magic, combative magic, etc.

One pattern that has emerged is the "specialized semi-mage."  This is a character who has taken a relatively poor AV in MIND, usually around a 6, and then used a very good Diff Mod (say -3 or even -4) in one or two spell skills, to become as good as a normal wizard in those areas but poor in all the others.  This seems at first glance to be a "loophole" in the system.  But it's not as bad as it seems.  In practice, this type of character spends 18 character points for an aptitude of 6 in MIND, then uses this approach to end up with a difficulty of 3 in a spell skill.  At this level the character can develop one skill moderately well, perhaps comparably to a wizard.  Remember though that those 18 character points were not a trivial amount; you could go from an 8 to a 4 in COMBAT with those same 18 character points and be almost a professional warrior where you would have been helpless.  In exchange for that much, the character gets one spell skill, essentially one part in 18 of the wizard's craft, and cannot even develop the Spellthrow skill needed to be an effective wielder of attack spells without paying through the nose.  More importantly, the character now must spread himself thin when spending development points.  In play this type of character has ended up, if anything, a bit disadvantaged over the specialists.

C.2.4 Skills

Spellcasting in RDI requires the use of 18 spell skills, listed below and denoted with a µ symbol.  There are also a few other skills, which are supplementary.  Depending on the world background, the GM may allow or disallow a few of the skills from the other magic systems listed here.  (For example, the various "Detect" skills in Appendix A, or the item-related skills, may be allowed.)

Develop these skills as you would any other.  A hint for getting the most out of your points: make a list of 5-10 of these skills you intend to eventually train in, and spend at least a point or two in all of them.  Then concentrate on a few.  Don't feel trapped by the few you start with, though.  If you decide later on you'd rather have developed a different one, don't "throw good development points after bad."  Start developing the other skills immediately and don't look back.

C.3 Magic Skills

Anti-Magic µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
This is the basic spell skill for spells of defense against magic.  Use this to create protection against magic, to resist magical effects like elemental heat and cold, and to avoid the effects of charms.  You can also use it to destroy the effects of magic, such as dispelling magic, draining a foe of spell points, or cancelling a spell being cast by someone else.

Art copyright  Lou Frank, used by permissionChanneling
  (C=MI, S=W, D=+1, U=-30)
  SIM: Circle Magic:1/3, Meditation:1/5
This skill is used to transfer spell points, or even spells, between characters.  (See section C.4.5 for information on the unusual use of spell points in the RDI system.)  Make a roll on the MM column of the maneuver chart, and multiply the number of points sent by the percentage result; this is how many spell points are transmitted.  The receiver must do this as well.  (Thus, both sender and receiver must have high Channeling skills to make a reasonably efficient transfer.)  The sender may not use this skill if he has any spell point loss.  When transferring spells, you are essentially casting a spell through someone else.  Effectively, you must channel as above, making sure enough spell points are received to cast the spell; it doesn't matter if the receiver can cast the spell himself.  The GM may allot bonuses if the channeling is at a predetermined time and/or place, or penalties if the channelers do not know the precise location of their partners.

Circle Magic
  (C=MI, S=W, D=+1, U=-30)
  SIM: Channeling:1/5
This skill is used for multiple spellcasters to cooperate on a single spell.  Each participant in a "circle" must be skilled in the appropriate RDI spell skill.  One of the casters is the "focus" and actually performs the spell; all the others "feed" skill to the focus.  Each participant (including the focus) must make a Circle Magic skill roll, modified by -10 per "feeding" participant.  The percentage result read from the maneuver chart is multiplied by each spellcaster's relevant spell skill's SV.  Results for all participating spellcasters are added together to yield the effective SV of the whole group, which is used to cast the spell.  The percentage each character obtained on the chart is also the percentage of the spell point cost for the spell that that spellcaster must pay.  Any fumble in the Circle Magic rolls will break the link for everyone, but failures only mean a specific spellcaster failed to link up.  If the circle's spell causes a spell fumble, everyone in the circle suffers a fumble result.  Make a dô roll for the whole group.  For each participant, multiply their percentage result by two and multiply this percentage by the group's roll; this is that participant's spell fumble roll.

Enchantment µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
This skill is used to cast spells that manipulate other spells.  (Destroying spells is done with the Anti-Magic spell skill.)  You might use this skill to control or enhance an existing spell, imbed a spell into a rune or scroll, create a magic item, save a spell for later, identify or manipulate a magic item, or control your own spellcasting abilities.

Enhancement µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
This spell skill is used to enhance the physical attributes of living beings.  You might use it to change the shape of yourself or someone else, grant the ability to walk on walls or breathe water, speed up a person's movement, or improve the senses of a person or being.  It's usually a lot easier to do these things to yourself than to someone else.

Forces µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
This spell skill creates and manipulates forces.  Telekinesis is the most obvious use of this skill.  In worlds where there are flows of essence, these are also manipulated by this skill.  You can use this skill to channel raw energy at a foe (like the Channels spells on Spell Law™'s Cleric Base lists).  You would combine this skill with others to do many things like picking locks, but many other things you could do with this skill are better done with another one, such as deflecting blows (best done with Shielding).

Gases µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
All spells that manipulate the gases in an elemental way are cast with this skill.  For example, controlling the winds, changing gases, purifying air, creating air underwater, and creating poison gases or electrically charged stun clouds, are all possibilities with this skill.

Harming µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
This spell skill is the opposite of Healing.  It represents the various evil magics of destroying the body, such as bringing plagues, body rot, physical curses, etc.  Most societies shun any practitioner of this skill.

Art copyright  Gregory Walsh, used by permissionHealing µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
This is the magic skill of mending bones, skin, nerves, and muscles, regeneration, treating and neutralizing poisons and diseases, and enhancing natural recuperative abilities.

Heat and Cold µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
This skill is used to control temperature, flame, and ice.  It could be used to create or dispel fire or cold, or heat and freeze things.

Illusions µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
Any illusions, such as invisibility, phantasms, magical disguises, auras, and other spells involving the manipulation of the senses for the purposes of trickery are the domain of this skill.

Liquids µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
You could use this skill to create, destroy, and control water in all its forms.  For example, you might throw a waterbolt, aerate water so people could breathe in it, call rain, calm waves, purify water, transmute water into wine, conjure water, or locate water in the desert.

Magic Resistance
  (C=MI, S=R, D=+3, U=0)
  SIM: none
This skill gives you a resistance to magic.  Not all GMs will allow you to develop this skill.  This skill's SV becomes the character's Resistance to Magic/Psi.

Mental Magic µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
This skill is used to manipulate the minds of yourself and others.  Telepathy and mind reading, scanning an area for minds, speaking into the mind of another, reading a language from another's mind, and controlling someone's memory are methods of manipulating the minds of others.  Making yourself able to learn or remember things exceptionally well, controlling your own dreams, correlating information at superhuman speeds, and controlling your own state of mind are methods of manipulating your own mind.

Nature µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
Skills related to manipulation and understanding of nature are grouped in this spell skill.  You could use it to communicate with animals, predict or affect the weather, manipulate herbs, call animals, or locate things in the wilds.

Shielding µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
Use this skill to cast spells of defense against physical attacks.  (Defense against magical attacks uses the Anti-Magic skill instead.)  You could create a shield out of force, deflect incoming attacks, make force armor, create a field that resists (natural) cold or heat, or give someone the ability to resist damage or poisons (neutralizing existing poison in someone's system would require Healing.)

Scrying µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
All informational spells can be cast using this skill.  Locating items, seeing or hearing distant things, identifying a person by their mind's imprint, enhancing someone's sense, predicting the future, seeing visions, or identifying magic items would be performed with spells in this category.

Solids µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
All the spells of manipulating solids are part of this skill.  Creations and disintegrations, transmuting elements, changing the shape of an object, weakening or strengthening, extracting elements from an alloy, warping, expanding or contracting, and shattering solids are possible uses of this skill.

Souls µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
This is the magical skill of controlling the state of a living being's soul.  It includes such things as putting people to sleep; creation, control, and repulsion of undead; charming and bewitching people; quests; mental curses; preserving the soul while a damaged body is repaired; etc.

Sound and Light µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
Magical control and creation of light, sound, lightning, and pure energy are performed using this skill.  You might create or banish light, cast shocks and lightning bolts, or change the color and brightness of light.  You could also silence an area, make a sound louder, make a sound seem to come from somewhere else, record sounds, or control where sounds travel.  There is the potential for overlap with the Illusions spell skill; but that skill emphasizes manipulations of the senses for the sake of trickery, not manipulation of essential sound and light.

  (C=MI, S=DW, D=-1, U=0)
  SIM: similar Spellthrow:1/4
This skill must be specialized for each type of attack spell or psion it is used for.  It would only be used for targeting physical attacks.  It is applied as a bonus to the attack roll, if the spell is successfully cast.

Time and Space µ
  (C=MI, S=W, D=special, U=-50)
  SIM: none
The ability to manipulate time and space with this skill might let you teleport, distort space, manipulate forces like gravity and magnetism, see through time, travel to other planes or summon beings from other planes, travel through time, or dispel conjured beings to their home planes.

C.4 Casting Spells

C.4.1 Inventing The Spell

Whenever you want to cast a spell, you must invent it in detail.  What does that entail?  You have to describe it to the GM, who may ask questions for more details.  The description can be as simple as naming a spell in Spell Law™ or GURPS Magic™, or it can involve a variation on one, or it can be a spell described from scratch.  Don't be afraid to invent something totally new.  That's the whole point of the RDI System!

Your GM may ask you a number of questions asking for details.  Most importantly, the GM may want to know how you intend to do it.  That's a tough question and the answer may have to be vague.  It's hard to describe where the line is between just saying "I'll make it happen" and describing the procedure in detail.  For instance, suppose you want to sober up a drunk person.  It's obviously easiest to use the Healing skill to accelerate natural healing procedures.  But what if you don't know that skill?  You might try to physically remove the alcohol from your target's bloodstream using the "purification" capabilities of the Liquids skill (accumulating the poisons in the person's bladder, perhaps).  Perhaps you could get the person to "sweat himself sober" by alternating heat and cold with the Heat and Cold skill.  You could even try to accelerate time around the target, so that three hours pass in as many minutes for him or her, using Time and Space.  There are probably other ways.

As you can see, you can use different spell skills to the same effect with different difficulties depending on how you do it, so your GM will use this information to figure out what spell skill to use and how difficult the spell is.  Clearly there are some spells that you won't really detail the operations of, such as a simple shield spell.  But there are spells where it may seem obvious, but doesn't have to be.  For instance, how do you cast a Friendship spell?  You might just fall back on the reliable Souls skill, but if you wanted to get specific, you might describe a spell which takes advantage of some neurosis of the target which makes it easier (e.g., if the target is somewhat paranoid it may be easier to cast an image of yourself as persecuted by the same people than to convince him you're a friend, because his mind is more receptive to that sort of thing).

Your GM will have to decide the level of the spell based on a comparison to the spells in Spell Law™, so you will have to specify the duration, range, and area of effect as part of the spell invention process.  For instance, suppose you cast a Silence spell.  One that lasts one minute is obviously not as hard as one that lasts an hour, and a 10' wide one is a lot easier than a 100' wide one.  Since many spells in Spell Law™ have variable durations or areas of effect (usually proportional to the caster's level) this will help the GM decide a level for the spell.

C.4.2 Assigning a Level

The GM then has a difficult job, one which is the crux of this whole system.  Based on the description of the spell and a comparison to Spell Law™ or a comparable system, the GM must assign the spell a spell level.  If the GM finds an identical spell in Spell Law™ s/he can just use its level.  Otherwise, a comparison has to be made.

If a GM doesn't have or use Spell Law™ another system can be used.  In this case, the appropriate value is the character level, in terms of a level-based game like Rolemaster™ or Advanced Dungeons & Dragons™, that would be needed to cast this spell.  For instance, if using Advanced Dungeons & Dragons™ as a reference, a Remove Curse clerical spell would be 6th level, because it takes a 6th level character to cast it.

Art copyright  Robin Wood 1992, used by permissionSince the characters can vary existing Spell Law™ spells in any way desired, the GM must compare based on how useful the spell is; but also, the method used should be considered.  If the character comes up with a clever way to use a force or power to accomplish some skill, the GM should be willing to let the character get an easier spell out of it.

Care must be taken to be aware of the whole story.  Suppose a character wants to deflect an arrow flying at a friend, but doesn't have the Shielding skill.  "No problem," she figures, "I have Forces, I can use that."  She then argues that it only takes a tiny force, perhaps a half pound, to knock an arrow off course, and therefore concludes that a simple first level spell will do.  (Using the Shielding skill the GM would conclude level 5 by comparison to the Deflections I spell.)  Sounds convincing?  Well, yes, but the problem isn't putting that half-pound of force out there, it's putting it in just the right place at just the right time.  If it were as simple as pushing with a half-pound of force, the caster could just knock the arrow out of the air with her hands (which can obviously exert a half pound of force) and be done with it.  So you see, there's a reason Deflections I was a higher level.

Suppose the player says, "But I have the Yado skill, can't I use that?"  Well, now, that changes things.  The spellcaster is now using the Forces skill to essentially put the force of her hands somewhere else, to deflect an arrow aimed at someone else.  Now the character might be able to use a simple first level spell and a skill roll on her Yado skill.  The GM would probably judge that she'd have a hefty penalty to her Yado skill roll because her training is in a very different situation, with the arrow coming at her, so she can see, hear, and feel it coming.  Also, Yado relies on split-second timing; if the time it takes her to utter the words of a spell are too long (and if she doesn't have a saved action, if using the IRIS Initiative System), she might not be able to do both things in time.  Perhaps if she prepared in advance and she used another spell to be able to see through the eyes of the intended target she could accomplish it all with no penalties.  Of course, one rarely knows in advance that a friend is going to get shot with an arrow.  But if it does come up...  (For instance, perhaps the friend is scheduled to be executed by "firing squad" in an hour, and the law says that if the arrows miss, the prisoner goes free.)  The point of all this is to think of spells as tools, and if someone figures out a clever way to use a tool in a special situation to make it more effective than normal, don't penalize them.

What happens when the player describes a spell that is in Spell Law™ but can be found on more than one list at different levels?  There's no good answer.  The GM should probably pick the one that he agrees with the most.  But if he has no preference, it's best to give the player the benefit of the doubt and choose the lowest level available.  Some GMs like to use the lowest level for characters who have developed a high degree of skill in a particular area and the higher levels for characters who only dabble, thus preserving the structure in Spell Law™ that allows a spell to be easier for some than for others, but this can be very hard to define when players refuse (very correctly) to set up their characters around convenient stereotypes.

In the following sections, the spell level will be represented by the symbol £.

C.4.3 Spellcast Modifiers

The first and most important thing the GM does with the spell level is to calculate a modifier to the spellcast roll.  To do this the GM simply plugs the spell level into a formula.  Here's the main formula:


This formula makes it pretty easy to cast low-level spells, but makes it grow harder and harder, faster and faster, as the levels increase.  For example, a 2nd level spell only has a penalty of 9, whereas an 11th level spell has a penalty of 144.

This formula works beautifully for levels up to about 10, but higher level spells are increasingly absurd to ever be able to cast.  For instance, a 30th level spell requires a skill of 1001 to have a 50% chance of success; a warrior with that kind of skill could be assumed to be able to conquer planets single-handedly.  If the GM doesn't like this formula, he might use a different one.  In this case the GM must announce the formula at the beginning of the campaign and stick to it.  Here are a few other formulae:

A dô is rolled, and your spell skill's SV is added in.  The results of the above formula are subtracted.  Additionally any spell point loss is also subtracted.  Finally, the GM applies any modifiers from Chart 14.2's Magic column, or any assigned modifiers.  Note that all spellcasting takes a single action; however, the GM may assign any delay modifier desired (when using the IRIS Initiative System) as long as he is consistent about it.

C.4.4 The Spellcast Roll

This roll is the spellcast roll, and it is indexed onto the Static Maneuver chart.  However, note that Fumble results will start at 25, not -5 as shown on the chart, for spellcasts!  Magic is a fickle force and we don't want spellcasters going over their heads without fear of retribution.

Each possible result is described below.  Note that some GMs may change a few details, and should announce the changes.

Art copyright  Doug Beekman, used by permissionExtraordinary Failure: The caster loses the ability to use magic for the rest of the day and takes two spell fumble rolls at +100.

Fumble: The character pays the full spell point cost and takes a spell fumble.  For the fumble roll, add twice the number of points under 25 the total spellcast roll was.

Failure: The character pays half the normal spell point cost.  The spell fails.

Partial Success: The character fails to cast the spell, but does not get charged any spell points.  She may try again next action.

Near Success: The character casts the spell, but there is something wrong with the way it works.  Perhaps it is a bit less effective, or it brings an odd side effect.  If the GM can't think of anything good, you may simply be required to pay double the normal spell point cost.

Unrelated Success: The spell fails and half the spell point cost is spent, but something else happens, perhaps magical, to the caster's benefit.

Success: You cast the spell at the normal spell point cost.

Critical Success: You cast the spell for free.  The energy comes from the world around you.

Extraordinary Success: Not only do you cast the spell successfully, and not only is it free, but you also do it much better than you expected.  If the GM can't come up with a good way to improve the spell (and it's rarely hard to do) he can give you +25 to your next two spellcast rolls.

C.4.5 Spell Point Costs

RDI uses spell points in an unusual and unique manner.  In the previous systems, you had a reserve of spell points you spent, and when you got to 0, you could no longer cast spells.  In RDI your spell point reserve starts at 0, and as you cast spells, it becomes negative.  This value is simply applied as a penalty to all spellcast rolls.

That means you can keep casting spells all you want, but as you wear yourself out, your penalty increases; effectively, this is the same as if your spell skills' SVs were dropping.  Thus, the chance of failure increases, as does the danger of a bad fumble.

Each time you cast a spell, the spell point cost is £x3.  You regain spell points at a rate of 3 per hour when resting (i.e., not using magic), or 5 per hour if you are sleeping or in a deep meditative state.  They can never get higher than 0.  Magic items similar to Spell Law™'s spell multipliers will simply multiply your regain rate (e.g., a x2 spell multiplier gives you a 6 point per hour regain rate).  Areas rich or poor in mana may change the rate as well.

These rules make no provision for any physical effects the character may suffer as a result of this.  It is assumed that the exhaustion of mana is not related to the exhaustion of one's physical energy levels.  If the GM wishes to have spellcasters grow weary, he can simply apply half the spell point loss as a penalty to all actions.

C.5 Effects of Spells

C.5.1 Interpretations

There's very little interpretation in figuring out how a certain spell affects the world in Prism terms as there is with many magic systems.  That's because the player defines the spell precisely, and if the GM has a question of interpretation he should ask it before assigning the spell level.

Of course, the fact that spell levels are assigned by comparison to Spell Law™ makes it clear that some familiarity with interpreting Spell Law™ spells is necessary.  In this case, the notes for interpretation in section A.4.6 will apply to a certain extent.

C.5.2 Elemental Attack Spells

Spells intended to produce elemental attacks will usually use one of the various charts provided in Spell Law™ or in Arms Law & Claw Law™ or Spacemaster™ for that purpose.  Of course, you may invent a new one (such as Stonebolt) or use a physical attack that is not strictly elemental (e.g. Flaming Arrow).  In these cases the GM should determine a similar chart to use, possibly at some bonus or penalty, and possibly with different crits.  For instance, the GM would roll Stonebolt as a Waterbolt with Krush instead of Impact criticals, and the Flaming Arrow would attack on the Composite Bow chart with an extra Heat critical two levels lower than any critical scored, plus the chance of igniting the foe's clothing on fire (depending on the clothing, of course).

C.5.3 Other Attacks

When characters cast spells that attack their opponents magically, rather than magically creating physical things that then attack, the procedure for resolving the attack is basically the potency roll procedure.

The spell makes a maneuver roll against its target (or targets).  The potency of such a spell is equal to the SV of the caster in the corresponding spell skill.  If the attack affects multiple targets it should be rerolled for each one.  Targets, of course, may use their resistance to magic/psi against this roll.

C.5.4 Maintaining Spells

When the spell is invented, you specified the precise duration.  In many cases that would be "Concentration," that is, as long as your character concentrates on the spell.  But in some cases it may be a specific time period.  You may have as many such spells going at once as desired, but you can normally only have one spell requiring concentration at a time, and casting another spell breaks your concentration.  Mental states such as meditation, or states caused by use of Mental Magic or Enchantment, may circumvent this.

You are allowed to cause spells with specific durations to end early at any time until it would have ended anyway.  This takes no effort or exertion, but it does take an action to perform, and a few seconds of concentration.  The same amount of time and effort will tell you if such a spell is still active or if someone has somehow cancelled it.

Alternately, if a spell is about to end, and you want to extend it, you can do so simply by recasting it.  As long as you complete the casting before the original spell ends, you will be at +25 to the spellcast roll, and if successful, you can have an uninterrupted extension of the spell (which can be vital for some spells like Life Preservation or Levitation).

Art copyright  Doug Beekman, used by permissionC.6 Magic Items and Alchemy

The RDI System does not include any rules whatsoever about magic items, except that they will be created by the Enchantment spell skill.  It is up to the GM to choose a system for this.  A traditional magic item system would be the one described in Spell Law™.  But there are many more possibilities.  Here are a few ideas for the GM to mull over:

C.7 An Example

Our hero is a brash young wizard named Andynn who is setting out on his first adventure.  He hasn't learned yet that casting spells that are too powerful for his meager talents can be dangerous.  His skills are 15 in Scrying and 12 in Enchantment.

Early in the adventure, the party comes to a situation where they need to see through a door made of wood with brass fittings.  Andynn's player describes his spell: "I want to be able to see through the door as if it were transparent, for a minute."  The GM feels this is a complete enough description and assigns a level of 3.  This is probably too high for Andynn, the GM warns, but the player decides to go for it anyway.

Andynn's Scrying skill is 15.  Since the spell is 3rd level, the negative modifier due to spell level is equal to three plus one, then squared, or 16.  Andynn has no spell point loss or other negative modifiers, so he rolls and gets a 30.  30 + 15 - 16 is 29, which is a failure, but not quite a fumble (only four more points and it would have been).  The spell point cost would have been 3 x 3 or 9 if he had succeeded, so it's 5 (9 / 2 is 4.5 which rounds to 5) leaving him with -5 spell points.

He decides to try again, and is lucky enough to roll high open-ended, a total roll of 124.  To this roll the GM adds his SV of 15 and subtracts the spell's penalty of 16 and Andynn's spell point loss of 5, for a total of 118, still within the range of success.  Andynn sees through the wood and saves his party from serious danger.  The spell point cost is 9, so his total spell point value is -14.

Later Andynn tries a simple detection spell using his Enchantment skill.  He simply wants to detect if there is magic in a certain item, which is clearly the same as the first level spell Detect Essence.  (Of course, in Spell Law™ Detect Essence occurs at 2nd and 3rd level as well on the various detection spell lists in the Channeling and Mentalism realms.  Andynn's GM decides that Andynn should get the first level spell because there is only one realm, so logically Andynn is the same realm as any magic that may be there.)

Andynn's skill in Enchantment is 12, and the spell's penalty is 4 (1 plus 1 is 2, which squared is 4).  Don't forget that Andynn is at -14 due to spell point loss, and he hasn't been able to rest.  Andynn rolls a 56.  56 + 12 - 4 - 14 is 50, so he fails.  Now his spell point loss is -16.  He tries again and rolls 43 for a total of 35 and fails again, bring his spell point loss to -18.  One more try, and he rolls a 85.  His player is elated -- that was a good roll -- but the total is 75, still failure.  Disgruntled, and realizing that with a spell point loss of -20 now his likelihood of success is low and dropping, Andynn's player gives up and rests.

The next morning Andynn is refreshed and ready, with no spell point loss.  He tries one more time, and rolls another 85.  This time, 85 plus his skill of 12 minus a penalty of 4 yields 93, which is a near success.  The GM rules that there's no way to know only partially whether there's magic in an item, so instead, she charges double spell point cost, so Andynn is now at -6 to all spellcasts.

He manages to find an hour of rest and works that back up to -3 before his next need to cast a spell.  Feeling cocky, he decides to try to cast a minor delving spell, trying to find out one specific fact about a magic item.  The GM rules that this is 5th level, worth a whopping 36 points of penalty, but Andynn tries anyway.  His player rolls a 46: a middle-of-the-road roll.  46 + 15 - 36 - 3 is 22, which is a fumble.  Andynn loses 15 spell points and takes a spell fumble at +6 (his roll of 22 was 3 points below the fumble threshold, so his fumble roll's bonus is twice that, or +6).  Andynn decides to give up on that spell.

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