Ok Something new to ponder upon that came in my way through discissions with Mystara fans in RL, and some here made me make the following statements
Spell finding and Research
by RobinIn the rules Cyclopedia an easy formula is made for PC's to use and determine the chance of studying new magic spells.
There is no variation used for Clerical spells, yet the system can be easily changed to encompass even that.
There is also no change between the rarity of magical spells, especially not with several new spells directly or indirectly added to the BECMI Mystara world with Gazetteers, Adventures and the change boxed sets of AD&D2.
I do not go further in to the D&D editions as that magic system used there is totally different and in my opinion unbalanced or only damage/protection orientated. I read them and my overall opinion comes to this conclusion. However, that said individual DM's might desire to include a spell from these editions as new researches/discoveries and place these on Mystara.
I made a reasonably easy system to encompass all these spells to become possible.
Chance of success
Changes of Learning existence of a spell or its understanding if exposed to, or understanding the researching based on a thought or concept, are the % chance to find below.
These may be decreased in low magic circumstances like wilderness by -10% to -5%,
in Rural farmlands by -7% to -5%,
Villages as -5% to +1% ,
and increased in towns and small cities by +2% to +3%,
medium cities or locations with a magic accepted culture(including shops) +3% to +5%,
large cities by +5% to +7%,
and close to an university or where many mages live by +7% to +10%.
Another adjustment the DM may imply is let the character exposed to a spell make an IN or WI check to understand the spell and add the amount of succes or failure(max 10) to the percentage of the chance to find
Clerics may learn of other spells from other Immortals by exposure to these as given by the same rates as mages yet must make a Wisdom check....and must be in good standing to that Immortal (IE Piety above 32!! and even then the Immortal may (often does) refuse to grant these spells as the spell might be too far off their doctrines(or they simply don't know it), uses a ritual they dislike, or say the cleric has enough good spells to use and grant only these instead. Rarely the cleric will become aware WHY a spell is not granted and must just accept (A DM must seriously check the Immortal and the spell, as well as the PC, its behavior (Piety) and Immortal's agenda/doctrines, and local circumstances the cleric is or will be exposed to before granting a spell. As opposed to mages who learn a spell and can cast it thereafter when willing, a cleric his spells can easily be withdrawn on the Immortal's (DM) decisions, and might be used only once, or under restricted circumstances as decreed by the Immortal (ie the DM based on the Immortal's decisions and the DM's game doctrine).
Chances of learning spells are per following formulas; (use IN for Wicca/Mage and WI for shaman/Cleric). Keep in mind There are restrictions. The Hollow World is the most known restriction where many spells are magically barred from being used at all, and can't be learned at all. Other spells are unknown, yet can be introduced to the resticted location and those willing/able to break the cultural restrictions due the same restricting Spell of Preservation will be able to learn these spells
Common spell (being any spell from the Rules Cyclopedia, in restricted circumstances where these spells are unknown the become Rare or very rare depending on circumstances and are controlled by the DM. NPC's and PC's must always be treated alike though.
chance to find;80%(+ or - adjustments as given above)
chance to learn spell;((IN/WI + Lvl) x 2) - (3 per spell level) %
Uncommon spell (being any spell from the Gazetteers, adventures, almanacs, accessories, or AD&D2 sets mentioned in the Mystara AD&D2 materials. Keep in mind some of these sources imply these spells are locally used and thus may be more common for the locals only; apply then the find spell changes as given above.Uncommon spells are also spells that are equal in game statistics to common spells yet have a different effect like Magic Missile vs Thornstrike, Fire Fingers, Frost Fingers.)
chance to find; 40%
chance to learn spell;.((IN/WI + Lvl) x 2) - (4 per spell level) %
Rare spell (being any AD&D1, or AD&D2 spell not mentioned or only suggested at in Mystara sources), I would also include In the Hollow World any Outer World spell to these, and I would include any Natural variation of common and uncommon spells (thus unaffected by the Radiance and functional in Days of Dread, or after the Radiance exploded). Keep in mind that after The Radiance exploded all magic is drawn from different natural sources (See Periods of Magic Evolution).
Like before the USS Beagle introduced a radiance tainted version of magic making magic easier to access than the original natural magic sources. Spell Casters must have (and had before 4000BC) a higher wisdom and/or intelligence to be able to cast these natural sources of magic at all.(absolute minimum 9 to 16....this depending on the natural source used, some sources are somewhat easier to learn others are more difficult then(more on this later in my 1752AC campaign information );
chance to find;20%
chance to learn spell; ((IN/WI + Lvl) x 2) - (5 per spell level) %
Very Rare or New Spell (This includes any spell in the Mystara sources as being a sole invention of a particular PC or NPC spellcaster, as well as any later edition D&D spell reconverted to Mystara. Keep in mind the DM has the last say in any of these spells if they are invented by Players and will adjust them accordingly to fit into the Mystara he/she uses. That means invented spells may become of a Higher level than the player or later D&D source gave, or will have similar yet resticted effects (components, range, effect, side effects);
chance to find; (10%
chance to learn spell ; (IN/WI + Lvl) x 2) - (6 per spell level) %
New spells are for the DM to decide which level they are, and which specific spell effects the spell has. So The player's character desires (for example) a small fire ball able to bounce over water. Then the DM decides based on similar spells which level, range, saving throws, area of effect, secondary effects, effects on succesful saves, casting time, and components. A general guideline herein will be if the spell is better in any of the statistics the spell resembles, it is at least 1 level or more higher than the based spell. If the spell is worse in any one of the statistics the spell resembles, it is the same level or 1 lower (never more).
So the player suggests a spell effect, the DM checks which spell it resembles and basing its decisions on that spell. He creates the statistics for all effects, etc. trying to keep gamebalance in check (a spell can never cause general more damage than spells of the same level, longer ranges will have longer casting times and shorter durations, etc). And then he informs the player of the final conclusion (last word is always the DM). Then the player rolls if he understands the principle of his research as per "Chance to find" % (this does not really cost any more money than studying in a suitable library for roughly 1 day per spell level. If this is succesful the player can roll to allow the PC really make the spell as per formula (costing 1000GP per level). if succesful the PC can then use the spell as any other spell.