A System of Magic

[Brimshack]

Okay, so let's look at a system for spell-casting in Worlds of Hurt. This is a high fantasy RPG, and I am just going to outline the magic system, partly for practice and partly in the hopes that someone will have the fortitude to read through it and give me their impressions.

The goal here in creating this system is to generate a rich tactical system using a relatively small number of spells. Casters are given a number of options over and above the choice of spells, and they must weigh the benefits and risks of these options when choosing the details.

The Magic Allotment

First, the number of spells a character may cast in a given game session is determined by a Crunch Stat, 'Magic'. Crunch Stats are purchased by spending experience points at a cumulative cost (Magic of 1 costs 1 x.p., Magic of 2 costs 3 total x.p., and Magic of 3 costs 6 x.p., etc.).

Spell Schools

The ability to actually cast spells is purchased through Special Abilities (also bought with Experience Points), a Minor Ability gets you 1 school of magic, and a major gets you 2. There are 6 schools of magic, each being defined in functional terms and kept pretty exclusive; divination, enchantment, healing, mind affecting, offensive, support.

So, a player buys points in Magic to generate the actual spells and buys Special Abilities to get schools of Magic granting her access to actual spell lists (and a player can only take 3 schools). Every caster automatically gains access to all spells in her any school(s) she has purchased.

Success or Failure I: The Roll and the Modifier

Success or failure in casting a spell is determined by rolling 3d6 and modifying this through a Functioning Stat. Sometimes this is rolled against a Target number (usually 12), and sometimes it is an opposed roll. The Functioning Stat will be a combination of 'Magic' and some other Crunch Stat:

Magic+Aggression = Magic Attack (used for Offensive spells). This is normally an opposed roll.
Magic+Presence = Mind Affecting Attack (used for Mind Affecting Spells). This is normally an opposed roll.
Magic+Focus = Magic Task (used for Healing and Support Spells). This is normally rolled at a Target of 12.

Note: Divination and Enchantment spells are sometimes rolled against a Target and sometimes as opposed rolls.

Success or Failure II: The General Spell Modifier

Now: There are no spell levels, and you do not need to memorize anything. You can use any spells from any schools you know until your Magic stat is exhausted. But each spell imposes a penalty on the roll, and the more powerful the spell, the higher the penalty. Healing is 1, Push-Em-Over is 4, Quickness is 5, etc.

Variables: The default range of all spells is 1". This may be increased in 3" increments. The default Area of Effect is 1 person. This may be increased in 2" increments. And most spells have a default effect which can be multiplied (for example Energy Attack does 1 point of damage. Now for every increment by which a variable is increased, the caster adds 1 to her penalty for casting a given spell).

The penalty for each individual spell is added to the total penalty for increasing the variables for the spell to get the General Spell Modifier (GSM) for the specific roll. The GSM is a penalty weighed against against the Functioning Stat of the caster, and the balance is applied to the die roll.

This creates a dilemma by which a caster must measure the benefits of tougher spells and/or increases to key spell variables against decreased odds of success.

Success or Failure III: Burning Actions for Bonuses

But there is one more potential modifier:

For every extra Action a Spell Caster spends casting a given spell, she gains a bonus of 1, and she can do this for up to 1 round per point of her Magic score. The number of Actions a Character has in a given round is determined by her Speed.

This creates a dilemma whereby a spell caster must weigh the benefits of extra time spent on a spell against the opportunity costs of spending that time on other things (and if she casts for more than one round, the risks of being hurt before completing the spell).

Example

So, imagine a spell caster, 'Uncle Hakeem'. Let us say that Uncle Hakeem wants to cast a healing spell, and he has a Magic score of 5 and a Focus score of 4, so he will have a Magic Task Bonus of +9. Let us say that he has a Speed of 3, and one of his buddies (an orc, named 'Bile-Brew') is 15" away from him on the battlefield.  Bile-Brew is badly injured (say down 22 out of 25 Durability Points and he is taking penalties due to the damage). Another companion (a Yoda-like creature named 'Goad') is 8" directly to the left of Bile-Brew, and that companion is a little bit injured (say 4 out of 20 points).

A Healing Spell does 1 point of healing per point on the die roll in excess of 12 (there is no effect to multiply here). So, if Uncle Hakeem only wants to heal Bile-Brew, he will have to take a penalty of -6 on his spell (1 for the Healing Spell and 5 for the range), which means if he pops the spell out in one Task, Uncle Hakeem will be casting at a +3, which means the odds are that he will only heal Bile-Brew for about 2-3 points. If Uncle Hakeem also tries to heal Goad, he will have to add 2 increments of radius (assuming he locates the spell directly between the two of them), so his bonus will only be +1, which means the odds are very low that Hakeem will accomplish anything worthwhile.

Now if Hakeem casts his spell for a full Turn, he will get a +2 Bonus for the extra actions spent on the spell regardless of the option he chooses. If Hakeem is brave, he may just declare that he is casting a Healing spell in the first round and continue casting at the end of his Turn. The gamble here is that he will not be hurt during the course of his Turn. If he ism hit while casting that will mess up his spell, and of course there is the possibility that either Bile-Brew or Goad will be killed before he finishes. But if Uncle Hakeem makes it safely through and finishes the spell when he Activates for a second Turn of casting, he may add a total bonus of +5 to his spell (3 for the first round and 2 more for the first two Actions of the second). He can add this to either option (healing Bile-Brew alone at a total bonus of +8, or healing both companions at a total Bonus of +6).

Final Comments

Offensive Variation: So, you can imagine how this would work with other spells such as offensive spells. Using the same spell you can hurt a lot of enemy a little or a couple enemy a lot. And if the enemy is foolish enough to let you cast unmolested for a few Turns in a row, well then your options will be substantially improved.

Mental Damage: Bear in mind with offensive spells there is an additional consideration. Enemy will take mental damage equal to the difference whenever they lose a roll versus an offensive spell. If the caster uses a spell to disarm an opponent, success means they drop their weapon and take mental damage in the process. But if a caster loses, then she will take Mental Damage equal to the difference minus her Focus score. So, the offensive caster can afford to lose, but not to lose big.

Aid: One general feature of this game allows any character to Aid another Character whenever she is within 1" of her companion when that companion must make a roll. When Aiding a Character must spend 1 point off an allotment determined by presence (another Crunch Stat), and she must go on Hold, thus losing 1 Action on her next Turn. In return she may add half her bonus (rounded high) on the roll in question to the Bonus of the person making the roll. Aid bonuses may be enhanced when characters share an affinity for one another. This creates two important options for casters

1) a bystander may help the caster with the spell. And bear in mind that Functioning Stats are usually a combination of two Crunch Stats. So, a Melee Fighter may not have any points in Magic, but if she has 5 points in Aggression, then she can give a +3 bonus to a caster. If the fighter has something in common with the caster (say that they are both beautiful, old, stalwart, compassionate, serve the same noble, etc.)

2) A Sheldman can be very useful in protecting casters while they keep going on a spell over the course of a couple rounds.Say, someone shoots at the spell caster while she is in the middle of a spell. A nearby fighter may choose to Aid the caster on her defence roll, thus giving her better chances of getting the spell off.

Greater Magic: For massive spells (think resurrection), the Spell Modifiers are huge (say -50, in some cases -100). Casters can cast most of these at leisure, so imagine a Magic Score of 10 and a Speed of 4, that's 40 total actions that can be spent on a spell.

Okay, that's it. Basic Question here is what do you think?

[Lance D. Allen]

Basic answer:

It's complicated. At least, it reads complicated. I have to confess that I had to stop my eyes from glazing once or twice while reading.

It does seem like it offers some decent tactical options for a miniatures battle. The level of complication would probably reduced with a greater understanding of the 'functional' and 'crunch' stats, which I imagine would come with reading the actual book. Illustrations would also help I think, though that's simply the hazard of text media.

The example helped a LOT in making it clear how it worked.

So, I'm pretty sure my answer is mostly non-useful to you. If your question(s) were clearer and more specific than "What do you think?" the feedback would be more useful.

[Brimshack]

Actually Lance, that was an amazingly helpful answer. I know it's not the most precise question, but first impressions are what I was driving for. And your response will help me a great deal.

[Brimshack]

Oh yes, the Stat system would normally come before the magic, and it takes more time than I put into the explanation above.

It works like this. Players advance their characters basic abilities by purchasing points in Crunch Stats (Aggression, Athleticism, Caution, Distance, Focus, Magic, Melee, Missile, Presence, Spirit, Swiftness). The Crunch Stats are then combined into Functioning Stats which serve as the basic modifiers to die rolls. So, for example Aggression modifies all Attack Rolls and Caution modifies all Defence Rolls. Now combine those with Magic, Melee, and Missile and you have 6 different functioning Stats: Magic Attack (Agg+Pre), Melee Attack (Agg+Mel), Missile Attack (Agg+Mis), Magic Defence (Cau+Pre), Melee Defence (Cau+Mel), Missile Defence (Cau+Mis).

The idea here is to give the player the chance to decide through her Stat purchases how much she wants to focus on a given form of combat as well as how much weight she wants to give to offence or defence. The system also creates symmetries of a sort insofar as a Character specializing in Melee Attack will also have a decent bonus on Magic and Missile Attacks. This may sound useless if the character does not have the ability to cast magic, but she can still Aid a Magic user, and if she is good at Offence, then she will be particularly effective when helping offensive casters.

So, for example a Character with an Aggression of 5, a Caution of 3 and a Melee of 6 would have a Melee Attack Bonus of +11, but a Melee Defence Bonus of +8. This is a melee fighter, but particularly one that specializes in attacking and killing her opponents. Turn it around and you have a tank or shieldman that is going to be hard to hit and good at aiding her friends on Defence.

[Wordman]

...the number of spells a character may cast in a given game session is determined by a Crunch Stat, 'Magic'.

One thing I noticed here. The sentence above and the phrase "the number of times a character may cast a spell in a given game session" mean slightly different things. It seems to me the latter is a less ambiguous description of what you turned out to mean.

Also, when you say someone is "fifteen inches" away, you are presumably using some special definition of "inches" that is not explained.

One issue with the system is using linear modifers on a roll that generates a bell curve. That is, each time you alter the GSM by one, the amount that one point changes the probably of success differs from the last one. For example, say situation A results in you needing to roll a 17 or higher and situation B results in you needing to roll 13 or higher. Say that, in both situations, you have a choice to add one to your roll. This always increases your chances of success, but they go up more in situation B (+1.9% vs. +1.4%).

Lastly, just for purity, the "cumulative cost" of Crunch" stats is technically called a "triangular sum".

Two things I do like about the system though:

1) While the explanation is complicated, once you understand the idea, actually using the system seems like it would work fairly quickly in play.

2) I like the idea of the "taking your time makes you better" idea, somewhat like how magic worked with the cards in Castle Falkenstein. The range and area changes are also vaguely reminiscent of Tri-Stat dX.

[Wordman]

Curse the inability to edit. Probability of success on 3d6 increases by about 9% when dropping the target from 13 to 12, and about 1.5% when dropping the target from 17 to 16, not 1.9 vs. 1.4 as I mentioned before.

[Guy Srinivasan]

Trading off time for effect is a fine tactical consideration, but it sounds to me like I would much rather play a nonwizard. I get to actually do something with my actions, instead of just waiting around, skipping my turn until I've powered up enough! Sure I make an interesting decision about the tradeoff, but then I lose the next 3 interesting decisions that a nonwizard gets to make 'cause decisions are tied to actions and I just spent my next 3.

(yes, sometimes you'll have to reevaluate due to an orc punching you in the face - is that the common case?)

This consideration is moot if spellcasting is fairly rare even for spellcasters on the battlefield. Do most wizardy folks also have a sword and spend most of their time in combat using it? That seems fine... I'm just worried about the obvious wizard build which ends up giving the player 1/5 the decisions of the other players.

Probability of success on 3d6 increases by about 9% when dropping the target from 13 to 12, and about 1.5% when dropping the target from 17 to 16, not 1.9 vs. 1.4 as I mentioned before.

Rolling over TN X on 3d6 is analogous to rolling over TN ((X-10)*2)+10 on 1d20 with crit-1 and crit-20. If you've set up your target numbers differently, then you're using a different scale of modifiers and TNs, and that's what's important, not the difference between 3d6 and 1d20. (Actually, that "times two" is "times 1.95" but close enough.) Here, for instance, your example translates to "Probability of success on 1d20 increases by about 10% when dropping the target from 16 to 14, and about 0% when dropping the target from 24 to 22." which is also pretty nonlinear.

[Lance D. Allen]

Guy,

I think you may be overstating your position, or not thinking about it the same way I am.

As I understand it, you can insta-cast at the base difficulty, or you can cast over multiple rounds, with each round adding a bonus to your chance of successfully casting it. "Cast now, or wait one more round?" is a meaningful choice. Do you risk failure, or do you risk being too late?

Also, I'm curious about something, now that I think about it...

If I'm casting for 15 inches the first round, then my target moves 10 inches toward me, can I reduce the distance to up my chances again? If he moves further away from me, can I increase the distance? Or do either of these circumstances cause me to waste the spell? Same question applied to other dial-able aspects of the spell.

[Guy Srinivasan]

I think you may be overstating your position, or not thinking about it the same way I am.

As I understand it, you can insta-cast at the base difficulty, or you can cast over multiple rounds, with each round adding a bonus to your chance of successfully casting it. "Cast now, or wait one more round?" is a meaningful choice. Do you risk failure, or do you risk being too late?

Entirely possible. Now that I see Aid takes up an Action, I'm guessing Actions are closer to a generic resource than something where the default is e.g. "attack every Action!". Basically since spells per session are limited, getting bonuses on them at the cost of Actions seems to me like it's far more useful than getting bonuses on e.g. some kind of an Attack action which, if it misses, burns only the used Action rather than the Action and a "spell slot". But if using Actions for plusses is the norm, than you're right, there's probably no potential problem there.

[Ashirgo]

My motto is "if all computations can be handled late at night and after two beers, the mechanics is great". In other words, my consideration here would be if your mechanics for magic needs just some streamlining (a simplification of maths, addition is simpler than subtraction, subtraction than multiplication etc). I see that it aims at a great precision, it is certainly not narrative: these additional details do seem to introduce some new tactical choices for players; I miss some flavour (I mean solutions that stem from the game world), however, but that thing is probably completely setting-dependent.  

What would you say about sth like "mana pool" as a thing to spend to get better effects, a substitute for "penalty to my roll"? You can also combine these two to get an interesting hybrid (but who knows if viable?)

"a rich tactical system using a relatively small number of spells" sounds like a definition of chess, I like that approach!

[Wordman]

Here, for instance, your example translates to "Probability of success on 1d20 increases by about 10% when dropping the target from 16 to 14, and about 0% when dropping the target from 24 to 22."

No, it doesn't.

For a d20, which produces a linear curve, my example would translate to something more akin to the following: probability of success increases by exactly 5% when dropping the target from 12 to 11, and exactly 5% when dropping the target from 19 to 18.

Since the d20 produces a linear distribution, using linear modifiers will have the same change to probability, regardless of the current target. Since the 3d6 produces a bell curve, the impact of linear modifiers depends entirely on the current target.

[trick]

Actually, in a sense Guy was right. 16 to 14 is exactly 10% difference. 24 to 22 is actually a 0% change because both of them are impossible.

[dindenver]

Brim,
 I think in a system like this, we should balance it against other forms of attack. For instance, if an archer aims for more than one action and gets attacked before firing, do they automatically miss and lose the arrow?
  Similarly, do melee attacks get a bonus to damage for exceeding their Target Number? If so, this seems to be a good balance.
  What about the limited number of spells. Will other characters be limited to what weapons they can use? That is the danger here, is that while the spell casters start out with potentially more versatility, their ability to grow is hampered more so than classes that rely on equipment for power increases. So, I feel like the artificial limits set on spell schools, etc. are working against your efforts to balance the game. I think the issue might be resolved by letting a caster cast any spell they can buy/find (just like a warrior can use any weapon they can buy/find). I don't know, I think the system youhave is pretty close on balance (better than other games).

  Also, for a wargame, this is an excellent writing style, it is concise and not open to much interpretation. For an RPG, it is a little dry, but I don't feel like these rules are really for an RPG, but for a wargame.

[Wordman]

Actually, in a sense Guy was right. 16 to 14 is exactly 10% difference. 24 to 22 is actually a 0% change because both of them are impossible.

He is right in that sense, but that sense had nothing to do with the point I was making. What I was disagreeing with was his statement that my "example translates to" those impossible numbers. My point has nothing to do with that. My initial 3d6 example talked about target numbers that were completely within the legal range of a 3d6 roll. I'm not sure where he got the idea I was talking about impossible numbers.

[Guy Srinivasan]

Wordman, you seem from other threads to be sufficiently knowledgeable about dice probabilities, so the following should make sense: to translate "rolling over 11 on 1d20" to "rolling over on 1d100", you shift the baseline by the difference in means to be equal, and scale the modifiers by the ratio of standard deviations to be equal. Thus: 11 = 10+1, 10-->50, 1-->5, and 50+5 = 55. So the analogous roll would be rolling over 55 on 1d100.

Similarly to find what roll on 1d20 is analogous to rolling over 16 on 3d6, you shift the baseline (rolling over 10) by the difference in means (10.5-10.5=0, no shift), and you scale the modifiers (16 = 10+6 so the modifier is 6) by the ratio of the standard deviations (sqrt(33.25) / sqrt(8.75) ~= 1.95), which makes the new roll rolling over (10+0) + (6*1.95) ~= 22 on a 1d20.

I'd like not to derail this conversation any further... it belongs in a thread like this, which we shouldn't necro... seems to not have a good place for discussion in this forum. For further discussion I guess start a thread somewhere else and put a link to it here?