As a player and a referee, my experience has been that for a class to feel different, the mechanics have to be different. Running one (maybe two) games, I appreciate smal changes or tweaks to existing classes to provide a new experience without having to master a new subsystem. In this post, I look at something similar to the venerable Chainmail magic rules. It may be more accurate to say that it is based more on reaction rolls/morale rules. For reference, the first spellcaster in the series (Saving Throw as Magic skill) is available here.

The best summary of the Chainmail rules I have found is here on Jeff Rients' Site. (I don't own DCC, so I can't speak to the DCC part of the post.) Essentially, roll 2d6 modified by spellcaster's level and spell level. If the result is 8 or more, the spell is successfully cast.

Starting with this mechanic, I want to make a small change. Chainmail did not have nine levels of spells and it seems that spell level and spellcaster level were more closely related than D&D. In other words, a 2nd level magic-user could cast 2nd level spells. Even if I am mistaken about it, the mechanic breaks down if I add the spellcaster's level to the dice roll for Swords & Wizardry. Not only that, there are nine spell levels instead of six. So here is my version of Chainmail-ish spell casting for Swords & Wizardry:

  • Roll 2d6 greater than or equal to 7+ Spell Level for success.
  • Half of the Spellcaster's level, rounded down, is added to the roll.

For those that care about numbers, this gives a first level magic-user about a 42% chance to successfully cast a spell. (Roll 2d6 greater than 8 with no adjustment to the roll.)This is close to the odds for the skill-based spellcaster I wrote about. Just like the previous spellcaster, the spell table is used to prevent spellcasters from launching high level spells before the standard magic-user.

Again, should the spell slot be lost for missing the roll? Not for this class. That leaves our 1st level spellcaster more chances to use the only spell slot.

Since the spell table is being used, we're still left with a class that is an unreliable spellcaster and somewhat less than the standard Magic-User class. We could adjust the XP table, but I want to add class features instead.

The skill-based spellcaster is able to make magic items that guaranteed spellcasting success. If I grant that ability here, I've only re-created the same class with a slightly different mechanic. That's too much the same, so let's try something else.

I do want to provide some kind of boost to the chances for casting spells, so let's do it by adding an extra d6 to roll and taking the best two. We'll say that this spellcaster can make astrological charts, leyline maps, or amulets to improve the chances of success. For the sake of convience, I'm going to call them amulets.

This leaves our poor 1st level spellcaster to improve only to a 68% chance, but as he/she advances, it will become much easier to cast lower level spells. A 2nd level spellcaster has an almost 89% chance of success to cast a 1st level spell. A 3rd level spellcaster has about an 81% chance of casting a 2nd level spell.

What this does is allow better chances without providing a static bonus. Even without gaining an extra die, as the spellcaster progresses casting lower level spells becomes much easier. At higher levels, the spellcaster will not need to pay for the ability to cast lower level spell. He or she will instead spend money to cast higher level spells. Specifically, we'll make it similar to last time: the cost of the improvement will cost 100gp per spell level and take the spell level number of days to create.

If a spellcaster spends 400 gp, he or she gets to add an extra die when attempting to cast a 4th level or lower spell. The amulet(or chart or whatever you call it) will only work for one spell regardless of success. In other words, if the spell still fails using an amulet, the amulet is lost.

At this point, we have a standard spellcaster with three tweaks:

  • Roll 2d6 greater than or equal to 7+ Spell Level for success.
  • Half of the Spellcaster's level, rounded down, is added to the roll.
  • Through making amulets, the spellcaster can add an extra die to improve chances of success taking the best two of the three dice as the result.

We're still left with a class with less spellcasting ability than the standard Magic-User class, so what else can be done?

Let's look at the standard Dispel Magic spell in Swords & Wizardry:

Dispel Magic
Spell Level: Druid, 4th Level; Magic-User, 3rd Level
Range: 120 feet
Duration: 10 minutes against an item

Dispel Magic, although not powerful enough to permanently disenchant a magic item (nullifies for 10 minutes), can be used to completely dispel most other spells and enchantments.

The chance of successfully dispelling magic is a percentage based on the ratio of the level of the dispelling caster over the level of original caster (or HD of the monster). Thus, a 6th-level Magic-User attempting to dispel a charm cast by a 12th-level Magic-User has a 50% chance of success (6/12 = .50, or 50%). If the 12th-level Magic-User was dispelling the 6th-level Magic-User's charm, success would be certain (12/6 = 2.00, or 200%).

Let's use this to provide a counterspell ability, but use a different  mechanic to determine success.

Instead of division, I will use subtraction to modify theroll, adjusting the target number by the result. For the examples listed, a 6th level spellcaster attempting to counter a spell cast by a 12th level Magic-User has no chance of success as he or she would have to roll a 13 to succeed. (12 - 6 is 6, add the adjustment to the target number to get 13.) Turned the other way around, the spell caster has an automatic success (the same as the Dispel Magic spell description). To prevent abuse of the power, The cost will be the highest level spell slot available. At higher levels, the spellcaster will likely cast the actual Dispel Magic spell, but unlike the standard Magic-User, he or she can attempt to dispel more than one spell by sacrificing the highest available spell slot available. For lower level spellcasters, this is a bargain, but the chances of success are much lower. Still, this ability is limited by the number of slots available on the spell table.

Looking at the four changes, we have:

  • Roll 2d6 greater than or equal to 7+ Spell Level for success.
  • Half of the Spellcaster's level, rounded down, is added to the roll.
  • Through making amulets, the spellcaster can add an extra die to improve chances of successof spellcasting
  • A counterspell ability that costs the highest level spell slot available.

I imagine this type of spellcaster being a Magic-Eater (similar to a sin-eater). Through a short ritual, these mages have a natural ability to negate magic at a cost of limiting their own ability to wield spells.

Next time, I'll look at a percentage based spellcaster.