Cthulhu based spell-like abilities for all characters

[Sravoff]

I was wandering through the new Call of Cthulhu d20 book. I found the spell system and immediatly fell in love. Arcane power decribed there is how I have always envisioned it.

However, I am nt planning on using sanity points, and many of the spells in there are a bit too dark for most characters. The spells fit nicely with BoVD but not in your average fantasy setting.

My thought was this. Make all spells available as spell like abilities.
Spells cast this way differ from "normal" spells in a number of ways.

1) Spells must be learned outside of class abilities. Usually involving a gold cost, a XP, and perhaps a feat (Not sure about the feat yet)

2) Spells cast this way are cast like the warlocks invocations. Cast in light armor, cast as a standard action, cause AoA.

3) Spells cast this way deal ability damage, whenever they are cast. A spell does damage equal to its spell level+1. A spell does damage to a stat according to what school of magic it belongs. (See Below.)


Abjuration: Abjuration spells deal damage to the Inteligence attribute.

Conjuration: Conjuration spells deal damage to the Strength attribute.

Divination: Divination spells deal damage to the Wisdom attribute.

Enchantment: Enchantment spells deal damage to the Charisma attribute.

Evocation: Evocation spells deal damage to the Dexterity attribute.

Illusion: Illusion spells deal damage to the Charisma attribute.

Necromancy Necromancy spells deal damage to the Inteligence Attribute.

Transmution: Transmution spells deal damage to the Wisdom attribute.

Feats
Arcane Lineage
Prereq: 1st Level Character
You begin play knowing one 1st level spell as a spell-like ability. This spell is cast according to these rules here.

Arcane Power Resistance
Prereq: Base Will Save +3
You subtract one from all ability damge dealt to you through the use of spell like abilities as described here. You cannot reduce the cost of a spell-like ability below one.
Special You may take this feat multiple times, its effects stack. Each time you take this feat, you must hav an additional +3 bas will save. ie. A character with a good will save can qualify for this feat at, 2nd level, 8th level, 14th level, and 20th level.


Learning a spell to be used in this way requires you to find a specifically prepared book, containing the spell used this way. Meaning you have to get the spell-like ability version of te spell, not the wizard's version from his spell book.
Understanding the book takes time. To learn a spell, yuo must know the language the book is written in, and spend one week of study per spell level. At the end of this week(s), make an int check DC 10+spell level. If you fail to learn the spell, you may spend another week of study, to try again. Each time you try again you recieve a +1 bonus to your roll.
Learning a spell also costs XP, you must pay 500xp per spell level.

Coments please?
-Sravoff

 

[Sravoff]

I forgot a few important pieces of information.

One, the DC for all spells goes off whatever stat is drained when used. So all evocations spells have a DC modified by str score.

Two, A minimum level required to cast a spell is double the spells level, minus one.
1st 1st
2nd 3rd
3rd 5th

and so on.

Third, Metamagic can affect thees spell-like abilities. However, when used, they increase the ability damage by the amount they would normally increase the spell level.
So casting a silenced second level evocation spell deals 4 damage to the characters STR.

Fourth, Caster level equals character level.
-Sravoff

 

[Cheiromancer]

How about some kind of skill roll to make the spell go off? It could be kinda funky- A DC 10 knowledge:arcana, and don't count ability modifiers (otherwise you hose abjuration spells). You need a number of successes equal to the spell level. Each +5 you make the roll by counts as an extra success. Each success causes a point of damage to the relevant stat. When you have enough successes/damage the spell goes off.

You can have as many other characters use aid other up to the level of the spell. They make the DC 10 check, and if they succeed you get another success (and pay another point of ability damage). It takes a round to make a check, or the casting time of the spell, whichever is longer.

With such harsh costs, I think that you could allow lower level characters to dabble with powerful magic. Instead of double the spell level minus one, make it so that to cast the spell your character level would has to be at least as high as the spell level.

A 5th level character with 8 ranks and skill focus would have +11 to his rolls. If he rolled a 19 or 20 he could get a 5th level spell off in just one round (DC 10 = 1 success, made it by 20 for 4 extra successes). It is more likely that it would take 2 or three rounds, or he'd stick to 2nd or 3rd level spells.

For symmetry's sake (and recognizing the importance of Constitution) I'd juggle the spells so that Abjuration is based on Dexterity, and Conjuration on Strength.

 

[Sravoff]

Actually allowing higher level spells earlier is a good idea. And as ou say, it should be a spell up to character level.

However I am not so sure about the roll. When I came up with this system idea, I wanteed it to capture the feel of complete pure arcane power, that takes it toll on the body. I tihnk the spells should be reliable, any time the character wants it, he gets it, but at the cost of ability damage.

What I realy wanted was for the spell schools to be based off the specialist wizards from 2e. But I lost my book.

Perhaps move them over to as you say, but that puts two schools on dexterity....
I'll swap conjuration to strength, and evocation to Dexterity. And give necromancy to inteligence, and transution to wisdom. That looks abit better. Only two of the schools rely on physical attributes.

-Sravoff