Wednesday, June 29, 2016

Caster Differentiation and Spellcasting Mechanics

I've given a lot of thought to casters.  I want them to feel different from each other.  Not just numberwise (wizards get +4 flarp while sorcerers get -2 flarp, etc) but with their own subsystem.

When I wrote the martial GLOG classes, I tried to do the same thing.  Assassins get damage bonuses the more facts they learn about an enemy.  Fighters track the number of kills they get with each weapon.  Rangers keep track of the largest monster they've killed.

Of course, the real place for subsystems is with magic users.  So that's one goal.  The other goal is to have them function very differently from each other, in addition to feeling different.  It's possible to have two convoluted subsystems that both take different paths to arrive at "3d6 damage, save for half".

So, here's what I've got:

Wizards are the most flexible.  They can learn and cast all the spells in the game.  Somewhat conservative.  Benefit the most from having time to prepare.

Sorcerers are the longest lasting.  While they can cast the most spells per day, they also have the narrowest selection.  They are hosts for their brain's spellhive, so they probably have the least control over the development.

Warlocks are the most powerful.  If it comes down a single spell, they can crank it up to 11, overchannel, and mop the floor.  They'll pay for it in blood, of course.

Clerics are the most reliable.  There's no difference between clerical magic and arcane magic--spells are just one of the many blessings that clerics receive.  The difference is that clerical spells aren't routed directly through the cleric, they're handled by heavenly powers who filter out a lot of the risk.  They have the support of a powerful familiar/patron, but they pay for that, too.

Saints are the most improvisational and the ones that hew closest to the divine.  They don't have spell lists, and instead call for miracles, which is a bit of a crapshoot modified by how close the requested miracle is to the deity's portfolio.  (Honestly, the whole thing sounds a bit dodgy, and I may scrap it.)

by Austen Mengler
The Casting Mechanic

I'm going to draw inspiration from WFRP, D6 Fantasy, +Mateo Diaz Torres, and the system I used in my earliest Eldritch Americana system (3d6 + mods vs DC, bad things happen on doubles or triples).

So wizards get 1 magic die per level.  At level 1, they have 1d6 sitting in their magic pool.  At level 4, they have 4d6 sitting in their magic pool.  (Class abilities max out at level 4 in the GLOG.)

Whenever they cast a spell, they can roll any number of dice from their pool. The dice are tallied, and any dice that come up 5 or 6 are depleted.  Depleted dice are removed from the pool, and not replaced until the next day.

The sum of the dice must meet a certain threshold for a certain effect.  Roll well, and your spell might be more powerful, similar to how DCC spells vary in power whenever they're cast.

  • Level 1 spell = 2.
  • Level 2 spell = 8.
  • Level 3 spell = 14.
  • Level 4 spell = 20.

Doubles on the dice signify chaos.  Triples signify corruption.  Obviously, you can't get doubles unless you roll at least two dice, so level 1 casters are safe.

Also, spells can fail if you only invest 1 magic die, but not if you invest 2 or more.  The threshold for reliability is the same as the threshold for chaos.

Let's do math!

With 1 Magic Die = 17% fizzle, 83% cast at level 1.
With 2 Magic Dice = 58% cast at level 1, 42% cast at level 2.
With 3 Magic Dice = 16% cast at level 1, 68% cast at level 2, 16% cast at level 3
With 4 Magic Dice = 3% cast at level 1, 42% cast at level 2, 50% cast at level 3, 5% cast at level 4

This seems about right.  A level 1 character's spells are going to fizzle 1/6th of the time, which sounds appropriate.  And higher levels character's will be discouraged from casting spells with only a single magic die invested--just invest another die and remove that horrible failure chance.

A level 2 character's spell is somewhere between a level 1 spell and a level 2 spell.  Yes, this means that a level 2 wizard can potentially cast a level 2 spell, but whatever.  That single spell might deplete all their dice for the day.  An increase in average power is balanced by unreliability.

A level 3 character can throw down all of their magic dice to cast a level 2 spell 68% of the time.  That's right in the middle.  Perfect.  They'll probably have one or two dice left over, which means that this is comparable to the 2/1 of vanilla D&D.

A level 4 character can throw down all 4d6 of their magic dice to cast what averages out to a level 2.5 spell, which also seems about right.  If they conserve a little, this is also roughly comparable to the 2/2 casting scheme of a vanilla D&D wizard.

These d6s also map pretty well to fireball damage.  A level 3 wizard can invest 3 magic dice to drop a 3d6 fireball (which is sort of like a fireball cast at spell level 2).

Wizards get safety casting.  Once per day, they can replace one of their rolled dice with a natural 1 (as if it was rolled).  (This is useful to avoid doubles/triples or to prevent a die from becoming exhausted.)

Warlocks get power casting.  Once per day, they can replace one of their rolled dice with a natural 6 (as if it was rolled).  (This is useful to avoid doubles/triples or to meet the next threshold for a spell.)

Sorcerers get natural casting.  Their magic dice are only depleted on a natural 6, instead of a 5-6.  (They get a lot more milage out of the same number of casting dice.  They're also at a lot higher risk for doubles and triples, but maybe their chaos/corruption tables aren't that bad?)

Clerics don't fuck around with any of this shit.  They get more many magic dice.  Their magic dice always deplete, and nothing bad happens with doubles or triples.  They can't spend more magic dice on a spell than their level (max 4).  I won't talk about them any more, since I have different ideas for them.

Anyway, you can already see that the themes of wizard/conservativism, warlock/power, and sorcerer/stamina are already emerging.  Good shit.

One hilarious effect of this system is that it means wizards can't prepare all of their spells at the beginning of the day, since some of their magic dice will be returning to them after they cast a spell.  Perhaps they can then spend 10 minutes to prepare any spell?  I imagine it going like this.

Level 2 wizard prepares a 2d magic missile.  Casts 2d magic missile (roll: 4, 6), which means that one of the magic dice is exhausted.  The wizard then takes a ten minute break with her spellbook and prepares a 1d speak with dead.

Which means that a wizard now has a good reason to haul their spellbook around with them, instead of leaving it at the dungeon entrance.  I love that.  Can we reinforce that bookishness more?

Wizard Ability: Book Casting.  A wizard can cast a spell directly out of a spellbook or scroll as if they had prepared it in the morning.  The spell returns to the spellbook/scroll in the morning.  Spells cast this way are always 1 magic die, and the wizard must have 1 magic die to invest.  This requires both hands (to hold the book) and the wizard always loses initiative.  If the wizard is damaged or disrupted while casting, the spell fizzles.

So now the wizard has a reason to carry around a big pile of scrolls.  And by leaving a die uninvested at the start of the day, a wizard can now cast any spell on the spot (albeit slower, riskier, and less powerfully than if they had prepared it in the morning).

Moving on.

Warlock Ability: Overchannel.  After rolling magic dice and summing the results, a warlock can choose to roll an overchannel die and add it to the sum.  They take damage equal to the result showing on the overchannel die.  The overchannel die can cause doubles and triples, as usual.  If the overchannel die causes a double or a triple, the warlock takes another 1d6 damage.

I'm not quite sure what to give the sorcerer.  I'm thinking beneficial mutation, related to what type of sorcerer they are.  Fire sorcerers become immune to fire and can eat anything flammable.  Fish sorcerers can breath water and talk to fish.  That sort of shit.

by Todd Lockwood
Sample Chaos Table

Here's the table for an enchanter.  Other wizard types will have other chaos tables.  Chaos tables are mostly bad, but occasionally helpful.

  1. You are made susceptible to charm.  Every command you hear functions as command (the spell).  By default, there is a 50% chance that language-using enemies are shouting something that can be construed as a command.  Lasts 1d6 rounds.
  2. You imitate another person or creature nearby, chosen at random.  You attempt to do whatever they do.  Lasts 1d6 rounds.
  3. You become empathic to all pain suffered around you.  Whenever a creature takes damage within 50' of you, you take 1 psychic damage.  Lasts 1d6 rounds.
  4. A random creature within 50' must save or you will both switch bodies.  Lasts 1d6 rounds.
  5. You immediately blab the worst thing possible.  You either tell the enemies about your secret weakness, insult the one enemy that can kill you, or embarass yourself horribly.
  6. You fall asleep, as the sleep spell.  Lasts until someone slaps you.
  7. You fall in love with whatever you are looking at.  (If this isn't already obvious, roll randomly.)  Lasts 1d6 days.
  8. All creatures in 50' are overcome with empathy, and will strive to talk over any disagreements.  Violence is impossible.  If you aren't in combat, the party will spend their time talking about their feelings and hugging.  The affected creature with the best Save rolls for everyone affected; save negates.  Lasts 10 minutes.
Sample Corruption Table

Whenever you roll on the Corruption Table, roll on the Chaos Table, too.  Go big.
  1. You gain 1d6 trauma points.
  2. You gain a random mutation.
  3. You gain a doom.
  4. You become an utter thrall, and will obey whoever has the highest Charisma as if you were affected by a dominate spell.  Lasts 1d6 days.
The first three entries are probably the same for all wizards.  The fourth is specific to the wizard's school.

by richard corben
worth clicking for a closer look

If you gain a doom, put a +1 next to the spell that caused it.  You now get +1 to the magic sum whenever you attempt to cast it.  Among other things, this means that you can now cast the spell with 1 magic die without any chance of failure.

Then you're done patting yourself on the back, this stuff happens.  

First Doom of the Enchanter: You become possessed by a random demon for 1 day.  This demon is based on [d4]: 1 lust and poison, 2 rage and fire, 3 gluttony and mutation, 4 ice and knowledge (lies).  The demon has no way to exit the body or manifest, but it is HD 8+1d6.

Second Doom of the Enchanter: You become possessed by a demon for a week.  This is the same demon as last time.

Third Doom of the Enchanter.  You become possessed by a demon permanently and your soul is devoured.  This is the same demon as last time.

Dooms are all school-specific.  A cthonomancer would eventually turn into a small mountain.  A biomancer turns into a cancerous mass.  A cosmomancer will eventually be abducted and impregnated by moonbeasts.

Dooms are meant to be a gradually rising meter for how fucked a wizard is.  This is why powerful wizards don't cast powerful spells all the time.  You get an apprentice to do that stuff.

If you survive the third doom, you're in the clear.  Dooms are designed to be a horrible, unavoidable death UNLESS the player actively seeks out a way to circumvent it.  In this case, the player will (hopefully) start looking for a way to kill that particular demon after surviving their first doom.

So dooms both (a) inspire players to go on personal quests to escape their doom, and (b) allow for character improvement narratively, away from the leveling system.  (I'm good at casting charm because the last time I cast it a demon burned it into my forebrain.)

You also stop getting those cute little +1s to spells, but whatever.  You escaped certain doom.

by Richard Corben

Sample Spells

Range: 50'
Target: 20' dia
Save: Half
Deals fire damage equal to magic sum.

Range: 200'
If you succeed on a ranged attack roll, you deal fire damage to the target equal to twice the magic sum.

Range: Touch
Duration: Magic sum / 4
You gain Fly 24.

Humble Hut
Range: Touch
Duration: 8 hours
You stack two stones atop each other and they grow into a hut.  This takes ten minutes.  Hut is 10' in diameter.  [8 or more]: Cabin is 20' square and has a locking door.  [14 or more]: Stone house has four 10' square rooms arranged as you please (possibly stacked into a tower), with arrow slit windows and a locking door.  [20 or more]: Castle built to your specifications; has a drawbridge and moat.

Range: Touch
Target: Object or creature
Duration: Rounds equal to magic sum
Target turns invisible.  Effect is dispelled if target moves or makes an attack roll.  [8 or more]: Effect is no longer dispelled if target moves.  [14 or more]: Effect is no longer dispelled if target attacks.

Magic Missile
Range: 200'
Save: None
You fire one missile per magic die, which unerringly hits its target.  Each magic die is a missile, which deals 1d6+1 damage to its target, each chosen independently.

Power Word: Kill
Range: 50'
Target: Creature
Save: None
If the magic sum is equal or greater than the target's current HP, it dies.

Summon Ix
Range: 50'
Duration: Magic Dice
An Ix is created at the point you designate and obeys a single command given by you at the time of its summoning.  The Ix is HD 1.  [+6]: HD +1.

Range: Touch
Target: 1 creature per magic die
Duration: 2 hours
Target creature gains the ability to breath water and loses the ability to breathe air.  Unwilling targets are allowed a save to resist, and another save if/when they lose consciousness from asphyxiation.

richard corben
click to embiggen


  1. This is cool, love the magic dice mechanic. Makes me want to tear out and replace the casting classes I have in my homebrew...

    1. I fucking love that these spam messages show up any time someone posts about D&D spells.

  2. Very very cool.

    One comment about the spell list: Power Word Kill seems to be inferior to Magic Missile in every respect (damage, range, all or nothing). Or does this interact with the Injury table in a way that means 0 hp is not the same thing as death?

    1. That's a good observation. I just wrote these as proof of concepts. Maybe rewrite it to make it an AoE called circle of death?

  3. Firebolt - Your level one and you cast this spell. You make your attack roll and succeed. You only have one die to commit so you roll it and get a one. Did you fizzle the spell? And if it is a 5 or 6 it depletes, right? I guess my confusion is whether you can fizzle a spell you also have to make an attack roll to land. Or is that the idea behind the increased damage? Risky but hits hard.

    1. Yes, a firebolt spell cast with only 1 die has a 1-in-6 chance to fizzle. And even if it doesn't fizzle, it still has to survive an attack roll. But this is hopefully balanced out by the increased damage (2d6 with one die).

      And of course, at higher numbers of magic dice, there is no fizzle chance, and the damage numbers become truly impressive.

    2. Thanks for the clarification. You have allowed non-casters the ability to cast from scrolls in the past. How do these new changes affect that seeing as a non-wizard would not have a d6 to commit to casting?

    3. Maybe a scroll gives them a single, free d6 to cast with, but incurs some risk (Int check or mishap).

  4. How would you say casters learn different spells? I had an idea that wizards lose max HP, sorcerers have to take them as part of levelling up, and warlocks have to ask their patron very kindly. Clerics are given them as a part of dealing with problems. Maybe?

    1. Hmm. I like frail wizards, but I like buff wizards, too. I sort of want to merge wizards and warlocks together, except that wizards get more versatility and warlocks get a panic button they can mash when they get in a tight corner, so they'd both learn spells the same way. I guess familiars can teach spells, so that's a venue for both of them.

      One idea I've been playing with is that the DM picks the clerics spells each day, since the cleric is just praying for guidance and doesn't really know what sort of miracles they'll be receiving.

  5. My name is dr.midnight from United States. I wish to
    share my testimony with the general public about
    A great spell caster called ( have done for me,
    this temple
    have just brought back my lost ex
    lover to me with their great spell work, I was dating this man called
    Steven we were together for a long
    time and we loved our self's but when I was unable
    to give him a male child for 5 years he left me and told
    me he can't continue anymore then I was now
    looking for ways to get him back and also get pregnant, until a friend
    of mine told me about this temple and gave me their contact email,
    then you won't believe this when I contacted them on my problems they
    prepared the items and cast the spell for me and bring my lost husband
    back, and after a month I missed my monthly flow and go for a test and
    the result stated that i was pregnant, am happy today am a mother of
    a set of twins a boy and a girl, i thank the temple once again for
    what they have done for me, if you are out there passing through any
    of this problems you can contact this great Dr for help listed below:
    Contact them...( whatsapp them on +2347037137208

  6. he bring my boyfriend back

    i am Mary and i want to thank Dr.henry olu for bringing back my ex boyfriend, we broke up for more than 8 month and he told me that he will never want to see me in his life again. i love him so much to the extend that i could not think of dating any man again, i was confused and depress due to the love i had for him.i did everything i could do to have him come back to me but all went in vain. so i decided to contact a spell caster, i did not believe in spell casting i just want to try it may be it would work out for me. i contacted dr henry olu for help,and he told me that he have to cast a love spell on him, i told him to do it. after 5 days my boyfriend called me and started to apologize for leaving me and also he told me that he still love me. i was very happy and i thank dr henry oul for helping get back my ex back to my hands. his spell is the greatest of all over the world, it was the love spell he cast on my ex that make him come back to me. all you ladies who want back their ex back i want you to contact Dr.henry olu for the return of your ex boyfriend and also your ex girlfriend he can also cast any kind of spell you want him to cast for you. his contact email is just try him and their will be a solution to your case.