Spellbuilding Part 1 – Simple Conversion

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The first part of the spell building system covers situations like finding a really cool spell that seems difficult to quantify or that you do not want to breakdown and rebuild. It is a fairly simple system to use spells from any OSR system, or retroclone OGL content. Before starting on that, here are the basic mechanics of the spell building system.

The system adds point values based on effect, range, duration, and any possible areas affected by the spell. The total is the spell's difficulty rating. Success in casting a spell is determined by rolling 1d20 + Intelligence score + Magic-Users's level to equal or exceed the magic-user's Saving Throw + difficulty rating. At the referee's discretion, a difficulty rating can be converted to a spell level for use in Vancian spellcasting. Like Cleric spells, converting a difficulty rating to a spell level is reversible.

This may seem like a mouthful, but to help with ease of calculation, I put Intelligence score + Caster Level on the character sheet. You'd think this wouldn't be a big deal, but it seems to make calculation easier. Since the Saving Throw already appears, it is just a matter of looking up the difficulty rating in the spell book.

In this post, I'll be taking OGL spells from various places and converting them to a difficulty rating.

Simple Conversion to a Difficulty Rating

Use the table below to convert spells to a difficulty rating:

S&W Spell Level Rating
Cantrips† 7
1 11
2 15
3 19
4 23
5 27
6 31
7 34
8 37
9 40

†Cantrips cannot do any damage. Using cantrips assumes the use of Tim Brannan's Cantrips for Basic Level Games system.

The difficulty rating in the table above is the midpoint for a spell level. Feel free to adjust the difficulty rating up or down by up to 2 points. In other words, a second level spell can have a difficulty rating from 13 to 17.

In looking for spells to serve as good examples, I looked for OGL spells from the LInks to Wisdom section on spells.

First, let's take a look at the Dreadcube (click the link for a full description). It is listed as a 7th level spell, so the new difficulty rating for this spell would be 34. It has multiple effects, so normally, I'd adjust the rating up, however, these effects can also potentially harm the caster, so I'll leave it where it is. OGL Link for Dreadcube

For those that wonder about the odds, let's take a magic-user with an INT 13 (the minimum score required to cast a 7th level spell). We'll say that the magic-user is at 14th level. The M-U will roll 1d20 + 13 (Intellegence score) + 14 (Caster Level) to be greater than or equal to 5 (Saving Throw at 14th level) + 34 for a total of 39. The magic-user will have a 45% chance of successfully casting the Dreadcube.

That seems a bit low, but 13 is the minimum Intelligence to cast a 7th level spell. Most Magic-Users for my players have an INT of 15 or 16 at least. Just for the sake of comparison, a 14th level Magic-User with an Intelligence of 15 attempting to cast this spell has a 55% chance of success.

Here's another favorite of mine from the Space Age Sorcery pdf, Pretervolve. (click on the link to download the free version). It is listed as Level 5, so the difficulty rating is 27. Seeing as there is a permanent effect after the spell wears off, I'd add a point to make the final difficulty rating a 28.

Again for the odds, we'll say that a 9th level Magic-User with an INT of 13 will cast Pretervolve. The M-U will roll 1d20 + 13 (Intellegence score) + 9 (Caster Level) to be greater than or equal to 7 (Saving Throw at 9th level) + 28 for a total of 35. The magic-user will have a 40% chance of successfully casting the spell.

Again, many characters will have a higher INT score. A 9th level Magic-User with a 15 Intelligence score has a 50% chance of success.

Section 15 of the OGL for the Pretervolve spell is:
Space-Age Sorcery, Copyright 2013, Hereticwerks; Authors James Garrison, Eric Fabiaschi, Porky

Here's another favorite, the Auric Devourer (read the post for the full description). It is listed as 1st level, so I convert the difficulty to 11. Since the description states that it is easy to cast, I'll bump it down to 10.

I'll come back to this spell another time when going through the building system itself, because it mentions other factors that will be covered later. It has a listed casting time and an area of effect.

Really quickly, a 1st level Magic-User with a 13 Intelligence will have a 50% chance of success to cast this spell.

Lastly, let's mention the Cantrips. They are not necessary at all, but I mention them here because they add something fun. Using the table, Blackflame starts at a difficulty rating of 7, and I'd leave it at that. Looking at other cantrips in the list, I would probably make Flavor a rating of 5. The key to using cantrips is that they cannot do any damage. Regardless of difficulty rating, any spell that does damage must be at least a 1st level spell.

A 1st level Magic-User with a 15 Intelligence (to represent most player characters), will have an 85% chance to cast Flavor and a 75% chance to cast Blackflame.

Using Difficulty Ratings with Class

Okay, I can turn a spell level into a difficulty rating. Now what? How does this work?

At this point, you could use the Spell Point system I mentioned to track the ability to cast spells. The cost of casting the spell is the spell level. Casting a spell deducts from a character's Mana and when Mana is zero, no more spell for you.

For your conveience, here is the table for Mana per level.

Level Mana
1 1
2 2
3 4
4 7
5 11
6 16
7 21
8 27
9 35
10 44
11 54
12 65
13 77
14 90
15 104
16 129
17 145
18 162
19 180
20 200
21 222

If the referee prefers, the traditional spell slot system can also be used.

Another alternative is to say that a Magic-User can attempt to cast a spell in his spellbook until it fails. If the Magic-User has Sleep in the spellbook, he can cast it until the dice betray him. For low level magic-users, this means that they can likely cast more spells per day, but it removes the need for bookkeeping.

Next time, we'll look at building spells based on effect, range, duration, and other factors.

The Next Big Project

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I don't know how far I will get on this, but I'm posting about it as a prod to get into the habit of writing instead of thinking.

For that reason alone, there will be no kickstarter. In fact, it will be free.

Seriously, though, the big project is a big book of magic for Swords & Wizardry. The book will include alternate options for magic, classes, spells, rules for spell research as well as magic item creation. Much of the alternate options for magic are already written, so that is not the difficult part. The rules for magic item creation are really straight-forward, but I haven't tested them, ergo, they may not be as straight-forward as I believe they are. The big challenge is finishing the spell building system.

Backing up a bit, here are some things to know about the material in the book:

Brace Yourself: There Will be Houserules

I have changes that range from modifying the odds for learning spells for characters that spend money to allowing scroll creation at 1st level. One example of a house rule is that everyone can use slings. The main reason is to provide a magic-user an alternative to throwing knives. One of the implications of that small house rule is that since many magic-users may use a sling, magic stones for slings become a type of magic item that appears from time to time. Since everyone uses a sling, these stones are quite useful.

Priests of Different Mythoi

This was bound to happen for me. In my head, the priests of Mitra have to be different from the priests of Asura. What would a priest for the God of Magic look like? How does a God of the Harvest send an "adventuring Cleric" into the world?

In 2e, Cleric spells were grouped into spheres which later became domains. Since the document will be OGL, I feel like I need to use the word domains even if I think "Spheres" in my head. Maybe I'm just getting old.

These domains are part of what makes one priest different from another. Another distinction involves alternatives to turn undead. Some variations are as simple as Turn Demons or Turn Orcs. Other variations are based on spell effects like Remove Fear or Protection from Evil 10' Radius. My favorite one at the moment involves the ability to provide healing that does not change the target's hit points. This includes spells like Cure Insanity or Ability Score drain, but not any of the Cure Wounds spells.

New Mechanics

I generally do not like to introduce new mechanics. I prefer to reuse ones that already exist. One favorite is a take on the Turn Undead table - variations of that appear in an alchemist type of class and in the psionicist class.

Yet, with the emphasis system aimed at creating more unusual spells, new mechanics open themselves up to all kinds of options. One of these options is a new type of magic item that allows you to permanently or temporary alter your magic-user's choice of emphases. My favorite is a spell that allows the caster to "borrow" an emphasis from its target.

I also have my own take on a spell point system. There is no subtraction involved. The saying goes that necessity is the mother of invention and I needed a system that was faster for my kids.

Wizards' Forms of Magic

The most powerful form of magic for wizards is Eldritch Magic. This is magic as presented in the S&W Complete rules. This means so-called unbalanced spells and spellbooks, spells as semi-living things in the wizard's brain, and all other kinds of Vancian goodness.

The second most-powerful form is Academic Magic. This is what "standardizing" magic looks like. Practitioners can create new spells with a greater degree of certainty, but lose the ability to re-create all the spells used by Eldritch Wizards. For example, an Academic Wizard can create a spell that sends a magic bolt at a target for 1d6 damage. The Academic Wizard, however, will not be able to match the range (240') of the Eldritch Wizard nor the ability to generate multiple bolts per level. For an Academic Wizard to generate a Magic Missile like spell, complete with a level-based effect on the number of missiles created, he or she would generate it as a second or third level spell instead of a first level spell.

The third most-powerful form is Everyday or Common Magic. This includes minor cantrips and illusions. These spells also include simple things like Mending objects, adding a foot to a length of rope, adding a spice to a dish and more. Don't let spells with minor effects fool you, shortening a length a rope can have deadly consequences.

Did You Have to Do Psionics?

Yes I do.

Eldritch and Academic Magics are available only to those that have the gift. Either a person can cast these types of spells or they cannot. For a person that wants to learn magic, but doesn't have the gift, the options are to either become a Cleric or make a deal with a supernatural power (i.e. become a Witch). Psionicists, called Disciples of The Path have found a different way. Clerics denounce disciples as atheists and heretics. Wizards consider them unsophisticated and crude. Witches consider them a hated enemy. Those that choose the Path, however, know that their powers equip them to deal with extraplanar forces malevolent and benign.

Other Things

There will be more spells and a handful of new creatures. As mentioned earlier, there is a spell building system. In addition to various player options, I hope to include many NPCs, including some that do not conform to any set of rules. (Bwa ha ha). There should be a whole slew of new magic items as well as artifacts. My hope is to provide something that may add a bit of spice to everyone's game.

Wish me luck, I'll need it. 🙂


The Spell Building Engine (Effects Only for Now)

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Update: 12-28-11: I changed the HTML tables into screen captures of the tables. Sorry for the awful formatting the first time. Sometime soon, I will have to address the CSS file on this site.

When I starting looking for a way to build spells, I was immediately drawn to various systems used in Fudge, EABA, and OpenD6. For reference, I also look to the HERO system. Thanks to the work of Killershrike, there is a HERO System translation for every D20 and D&D spell into the Hero System.

Why not build something like HERO? Like everyone else, my time is limited and I don’t forsee the ability to generate spells using such a detailed system. I love it, but not many of my friends do, especially my casual gaming friends.

For elegance, I don’t think anything beats the EABA system. Add a few numbers and you can create just about anything. I bought EABA Stuff some time ago and I love building things with it. What I’ve found with EABA, however, is that spell effects are underpowered when compared to some D&D spells. For example, a spell like Magic Missile doesn’t feel like a first level spell when built with EABA. It feels like something wielded by a much more powerful mage. (Purify Food and Drink, however, does feel appropriately low-level. I like how EABA’s version of Purify Water can be used to distill alcohol.) The biggest hindrance to using an EABA type of system would be recreating the Universal Table without infringing on Greg Porter’s rights. The table is the equivalent of Product Identity for EABA.

Any system for FUDGE is a lot of fun, but really narrative. I love narrative systems, but the Arcanist doesn’t seem a good fit for a narrative systems. Arcanists are skill-based mages. Working magic is like working leather – there is skill and technique that come together for a finished product. It is replicable and reliable. Just an ethos speaks to me of a more mechanic system with some amount of fiddly bits. In the end, I think a system like four-by-five could work, but OpenD6 provided a platform that feels closer to what I’m looking for.

What about OpenD6? It covers a lot of ground like HERO, but has the simple math similar to EABA.

It does have subtraction, which leads to issues in any building system. For example, an early version of Erin Smale’s Perfect Class document allows the building of a class that requires 0XP to advance in levels. The same is true in the OpenD6 spell building system – with enough money or time, you can effectively cast spells for free. I built a version of the D20 cantrip Ray of Frost that just 0 points to cast. Granted, it took gestures, material components, verbal components, a long time to cast compared to other cantrips, and the ray moved so slowly that the ray could be dodged easily. You may say that such a spell makes “free” casting useless, but with a guaranteed 1d3 damage and low skill required to cast it, you could see armies replacing archers with a bunch of folks that only know how to cast this ray. When there are a couple hundred bolts of frost coming at you, they are difficult to dodge. Sure it would be expensive, but a heck of a first wave attack as armies marched toward each other on the field of battle.

So I had to do a little hand waving and say that all spells cost at least one spell point. This prevents player abuse, though a good GM should be able to mitigate this kind of abuse without resorting to such a rule.

Another issue with the OpenD6 system is that the system requires several pages to explain. I haven’t streamlined past this issue yet. However, I hope that releasing this Alpha will generate some ways to streamline it further.

There are about thirty points of manipulation in the full OpendD6 system and that seems like too many. The simplified system in D6Fantasy has about six or seven and that feels just about right, though I am currently using more. (I’m not looking at it right now, so I’m pulling these numbers from memory.) I have about nineteen criteria now, but any given spell only uses five or six. Many of the categories are only there for specialized spells.

One other place of complexity is determining a value for the basic effect of the spell. Some effects are easy to chart – what’s the value for a spell that does 2d8 damage? (12). How about a value for adding +2 to Hit Bonus? (18). How about for manipulating 2 pounds of material? (2).

Other effects are difficult to chart. What is the value for the effect of a spell like Air Walk? (Not even killershrike.net translated this one.) For Air Walk, specifically, walking on air like walking up and down a staircase is difficult to describe in terms of effect. Moving a man-sized creature upwards, and horizontally but not all at once and only about three feet at a time in both directions. Levitation is moving a something upwards. Teleportation is moving something in three-dimensional space. You can measure distance and mass of the object moved. Air Walk, though, is not really Teleportation when you take a step to move.

Rather than attempt to calculate an effect for everything, I decided to make this a feature of one of the Mage classes. An Arcanist, a mage that can only use spells generated by the spell building system, can never cast Air Walk. A Wizard or Thaumaturge, however, could. Since the other two do not quite see magic as a skill, they can cast spells outside the artificial boundaries placed on magic by the Arcanist. So, yes, the Arcanist can generate spells with identical effects on a reliable and repeatable basis. However, the cost of this stability is placing artificial limits on what is possible with magic.

So after all this rambling, I’ll get to the point.

  • The spell building system is roughly based on the OpenD6 system.
  • I’ve removed some of the options in an attempt to address the “subtraction” issue I mentioned earlier and to simplify the process slightly.
  • I have also translated the OpenD6 Fantasy Spells as written, into a form that will work with Andras, as should work easily with any retroclone.
  • I have a lookup table that determines values for mass, time, distance and speed. The original OpenD6 table used meters for distance; my table, however, uses feet.
  • Determining a value for effect takes the most time. There are lots of guidelines and things for determining the value.

Determining the Effect

So what are the guidelines for determining an effect? Let’s get the simple ones out of the way first.

For Every +1 added to a skill score, the cost is one point. So to add 10 points to a Rouge’s Pick Pocket skill, the cost is 10 points. To add 8 points to a Mage’s Alchemy skill, the cost is 8 points.

For every +1 Bonus to Hit, +1 Bonus to Damage or -1 to Armor Class, the effect value is 9 points. So if a spell has the effect of granting a -2 AC bonus to its target, the effect value is 18 (2 times 9).

For Bonuses to a Saving Throw, a +1 Bonus costs 6 points. Every additional plus after that costs 3 points. So if a spell provides a +4 Bonus to the Breath Weapon saving throw, the cost is 15 points. (6 points for the +1, and 3 points per extra ‘plus’ which is 9 points. 6+9 = 15).

For Bonuses to an Attribute, a +1 bonus costs 4 points. Every additional plus after that costs 2 points. Due to the nature of Exceptional Strength, any Bonus strength steps through the 18.01 through 18.99 per the Strength table, even if the target is not a Fighter. So, to provide a +2 increase in a target’s Wisdom score, the cost is 6 points. (Four points for the +1 and two points for the additional plus.) To increase a target’s Strength by 3 will cost 8 points. However, if the target already has 17 Strength, the final result will be 18.51 Strength, not 20.

For everything else, there are two charts. This is the first one:

Damage: This is pretty straightforward. The effect value of a spell that does 1d8 damage is 6. Any entry with a blank space means that there is no correlation. So a damage based effect will never have a value of 7.

Attribute: This table represents the cost of imbuing the value of an Attribute on a target. This is used in two different ways. The first way represents creating a golem or other automaton. To imbue your creation with the following stats; STR 19, DEX 8, CON 8, INT 5, WIS 8, CHA 8, the cost is 30.  The other way to use it is to imbue a target with a specific attribute value. For example, a spell that imbues the target with the strength of a Titan (25) costs 24 points.

Skill Score: This is for imbuing a specific skill score on the intended target. Keep in mind that Skills in Andras are not like skills in d20. You can do stuff that’s not listed on the character sheet. Skills are class specific abilities, not a measure of what you can and cannot do. For example, a mage could create a spell that provides the target the ability to any one of the Rogue skills or use the Bard’s Lore skill.

d% Success: This column is identical to the Skill Score column, but the format is expressed in terms of percentage chance of success. So, to imbue the target with an ability that provides a 86% chance of success, the value is 15. This is exactly the same as imbuing the target with a Skill Score of 23. This column is also used to get the effect number of Detection spells like Detect Magic, Detect Invisibility, Detect Life, Detect Undead, etc. Since most detection spells provide a 100% chance of success, the effect value for most detection spells is 22.

Saving Throw: This column represents providing someone with a specific Saving Throw score for any one Saving Throw category. The numbers correlate to the d% Success column. This can also be used to provide a specific saving throw versus a specific effect, for example, a Saving Throw against fire, psionics, ice, etc. This can also be used to calculate immunity. For example, to cast a spell that makes the target immune to fire, the effect is 22. This can also be used to provide a Saving Throw to spells that normally do not allow saving throws.

Hit Dice: This column represents the total Hit Dice for the creature(s) summoned. This column is used for summoning a 7 HD elemental, but not used for creating a 7HD golem or automaton.

The last table covers time, distance, mass and speed. It is also used for more than determine a value for the effect of the spell. It is also used to determine the range, duration, and speed of the spell. Note that it does not cover volume. That is covered in Area Effect criteria in the spell building system.

This can take a bit of getting used to, so here are some walk-through examples.

Lets say that I want the effect number of 30 seconds. I find 30 on the chart and then look to the left to find its value. The effect number for 30 is 7. Since I am measuring seconds, I do not have to adjust the effect number.

Now let’s say I want the effect number of 30 minutes. Again, the effect number for 30 is 7. Looking at the chart, it says that minutes requires a Plus 9 adjustment. So I add 9 to the effect number 7 to get 16. The effect number for 30 minutes is 16.

Let’s say that I have a spell that affects 2 gallons of something. On the chart, I see that the effect number for 2 is 1. Then I see that the adjustment for gallons is plus 11. That makes the effect number for gallons 1 + 11 or 12.

Let’s say that a spell enables the target to move 60 feet per round. Looking on the chart, the effect for 60 is 8. The adjustment to indicate feet per round is Plus 5. Therefore the effect number for moving 60 feet per round is 13.

 The Magic Bullet

Finally if all these tables do not help you generate an effect number for what a spell does, look at spells already created. Multiply the level of the spell by 10 to get the desired effect.

There are more guidelines for Charm, Control and similar spells, but that will be in another post. Let me know what you think of this system so far. All feedback welcomed.