Wednesday, July 25, 2012

hybrid Chainmail/DCC spellcasting

Rolling dice to cast a spell goes back to Chainmail.  Here's the basic 2d6 chart:

2-5 Fail
6-7 Delay
8-12 Success

-1 for a first level spell, -2 for a second level spell, etc.

+1 caster level 1-2
+2 caster level 3-6
+3 caster level 7-8
+4 caster level 9-10
+5 caster level 11+

I may have that level chart slightly buggered up, as I'm doing it from memory.  A bunch of my gaming stuff is packed at the moment.  Also, note that the Delay category refers to the spell going off one Chainmail turn after the casting.  In my games I'd probably rule that the spell goes off the following round, provided nobody disrupts the casting in the meantime.

Anyway, even if you are a pretty strict Vancian adherent there's still lots of uses for a chart like this.  A moth eaten scroll with an incomplete spell.  Some joker with read magic trying to cast a high level spell directly out of a spell book.  Someone attempting to cast an Arduin spell that's rated a spell level beyond the scope of the rules you normally use.  Basically, any situation where the casting is less certain than normal conditions.

For DCC-style "you must roll for every spell" shenanigans, just add a "1 or less" category that sets off a spell fumble and an "oversuccess" result on a 13+.  While I don't mind making up spell fumbles and oversuccesses on the fly, a couple good rules of thumb for the latter might be in order.  Something like this:

  • Any spell with a variable based on caster level gains +1d6 levels.
  • Spells with no such variable double range, duration, etc as appropriate.
  • Magic Missile gains one bonus missile for each point over 12 rolled.

If you want caster Intelligence to figure into the roll, here's a chart for that:

Int 3: -2
Int 4-8: -1
Int 9-12: no modifier
Int 13-17: +1
Int 18: +2

These are the standard stat mods for BX D&D when applying a modifier to a d6 or 2d6 roll.  See Initiative Adjustment for Dex or Adjustment to Reaction for Charisma.


  1. You could bolt on so many fun things with this system.
    A lock of the target's hair: +2
    A drop of the target's blood: +5
    Use the target's true name: +5 and they get no save
    Using your own blood as a conduit for the spell: +1 per point of self-inflicted damage

  2. I love those old casting charts and variants.Spell casting being uncertain adds to the game and reduces the impact of MUs a bit.

  3. Someone attempting to cast an Arduin spell that's rated a spell level beyond the scope of the rules you normally use. Basically, any situation where the casting is less certain than normal conditions.

    I'm currently mulling over ideas for handling the alien magic of the ancient "Architects" of a science fantasy megadungeon, so this is food for thought, and very timely. Thanks!

  4. I too am looking for a means of destabilizing spell casting in a setting I'm trying to get on its feet, specifically concerning clerics.

    This is a great place to start

  5. It's a great system to use for a grittier feel to the game as well.

  6. DCC made the knock spell interesting. So it will always get a thumbs up from me.

  7. Anonymous5:19 AM

    If DCC had one standard spell table like this (and a half-page of buulet point examples), instead of multiple spell-specific tables, I would have been much more interested...

    I've been considering adapting the Chainmail table for clerical powers, with clerics calling upon their faith/deity instead of memorising spells (of course, mages use spell points)

  8. I like this tinkering that mixes old and new. Also I have been thinking a lot of making spell casting something you can fail as nature of the game always changes when fireballs and lightning bolts come avaible as problem solver.

  9. I'm currently using a variant of Chainmail to power my new version of D&D, though it's a bit different from yours. However, nice to know I'm no the only one exploring this option!
    : )

  10. In case anyone wants the original table, it's here: SPELL COMPLEXITY CHART

    Seer = 2nd level
    Magician = 6th
    Warlock = 8th
    Sorcerer = 9th
    Wizard = 10th

    ...which is all rather strange, really.

    At any rate, rolling for spells is fun. The rest is just details.

  11. I have recently gotten hold of an old TSR Conan DM screen and it has this system on it. I had been considering a roll to cast system with criteria and with a chance to recast. This system can be so easily adapted to bring in all sorts of mods. I am gonna cobble something together and put it on my blog.

  12. Jeff,

    I am really interested in this hack. I am doing a post about it on my blog

    Have you been using this in your games? How has it been working?