Skill Based spell casting, Balancing

[Uber Dungeon]

I just recently read a few threads about skill based spell casting, Including a few Anime based rpgs with that sort of spell casting.
I discussed it with my group and we are going to use a skill based spell casting, I wanted to keep it simple.

What we discussed.
-All Spell levels (1st-9th) would be available to a first level wizard. Who could buy a scroll or find some way of getting said spell into there Spell book.
-You would be unlimited in how meany spells you could cast per day.
-The skill check would be Spell craft DC: 10+spell level Squared, There would be no penalty on a successful check. (I noticed that skill casting systems have drain) A failed check would result in non-lethal damage.

Spell level----Check----damage if failed
1st------------12----------1D4
2nd-----------14----------1D6
3rd------------16----------1D8
4th------------18----------1D10
5th------------20----------2D6
6th------------22----------2D8
7th------------24----------2d10
8th------------26----------4D6
9th------------28----------4D8

-For every 5 the check is failed by an extra die would be added, So if a wizard cast a 9th level spell and the result of that check was 8, he would take 8D8 non-lethal damage.

My group seemed quite fond of this idea, that in a party killing situation they could cast a 9th level spell to tare there enemy asunder while sacrificing there own life for glory. Or as a cleric attempt to resurrect a loved one at the risk of sacrificing them selves.

As for metamagic, they would be available to any caster who meets the prerequisites. If it adds a +1 to the spell level it will add double that to the check instead (+2 to the spell craft check)

Anyways, this is about as far as I discussed this with my group and they are stoked to try it out. My biggest concern at the moment is the balance of the spellcraft check.

Then I would add a feat that allows a spell caster to count a chosen spell casting class level as there rank for spellcraft, or I may just give that feature to all spellcasting classes.

Thoughts? suggestions?

 

[Dandu]

2nd level Warforged wizard:

Ranks in Spellcraft: 5
Ranks in K. Arcana: 5, +2 synergy bonus to Spellcraft
Int: 18, +4 modifier
Skill Focus: Spellcraft
Bonus to Spellcraft: +14

Immune to non-lethal damage.

2nd level Cleric:
Ranks in Spellcraft: 5
Ranks in K. Arcana: 5, +2 synergy bonus to Spellcraft
Skill Focus: Spellcraft

Bonus to Spellcraft: +10

Guidance of the Avatar, Divine Insight

Cure Minor Wounds

 

[Empirate]

Translation, and abstraction: in D&D, it is really, really easy to boost skills through the roof. Moreover, the binary nature of skill checks and the great variance of the d20 roll make any skill-based casting system that relies on D&D's basic skill system a swingy thing at all times. Making all spell levels available from level 1, with just a skill check required, is an idea so bad it makes AEDU look favorable in comparison. My advice: forget it.

Reasoning: boosting the skill check DCs, or making certain options for skill enhancement unavailable, or any other way of limiting available spell levels based on character level, just beg the question: why change the original at all? NOT doing those things, on the other hand, just opens the door to abuse (and tears down all the walls around that door, too).

Tangential thoughts: how do you make sure nobody picks cross-class Spellcraft ranks? Why do Wizards, Clerics etc. have to pick Spellcraft ranks to cast in the first place (just a skill tax this way)? And have you ever looked up Tome of Magic's Truenamer, which tries to do what you are trying to do, and even though the designers invested some thoughts, the class is still broken (and not in the good way) beyond all attempts at fixing it?

 

[Nagol]

The ease of achieving bonuses in 3.5 looks like a feature for high-level casting though since a 9th level spell has a DC of 91. It's hard to imagine a 17th level character hitting that without coming up with a special sequence of boosting pre-casts (or equivalent magic items). A basic 17th level character's Spellcraft would be around +40 ( 21 from ranks, +10 from attribute, +3 from feat, +2 from synergy, +4 fudge factor) and needs to roll a 51 of the d20.

Functionally, the DC calculation means if you can conceivably cast a Nth level spell, you can't fail casting a N-1th level at around 6th spell level.

For first level characters:
5th level spells are just barely in reach although a strategic design and pre-casting boosts would be desired to improve the odds.
4th-level spells are about 50-50.
3rd-level spells are simple to cast having a DC of 19; taking a 10 would generally achieve success.
Most casters will succeed at 2nd level spells if they roll a 1 on the check.


It's hard to critique the idea without understanding what you want, but the above feels very different from base D&D.

I'd recommend increasing the base difficulty to 20 and reducing the maximum difficulty to 60-70 with a linear increase based on spell-level if you want a game closer to a D&D style.

Say Casting DC = 14 + 6 * spell level (20, 26, 32, 38, 44, 50, 56, 62, 68)

 

[N'raac]

Is the intent 10 + spell level squared (as written, which makes the DC for a L9 spell 91) or 10 + spell level doubled, which the chart shows, so DC 28? That's a pretty significant difference.

The use of Spellcraft greatly favours the Wizard, who uses its skill stat as his casting stat and typically buys the skill anyway. MAD is forced on other spellcasters who need their casting stat to be 10 + Spell Level (I assume that does not change) and need a boosted spellcraft skill.

Unlimited castings also changes the ground rules. Dandu refers to Cure Minor Wounds, which at 0 level appears to have a 10 DC and less than 1d4 nonlethal as a penalty for failure. It should quickly be autosuccess, so out of combat, everyone will be healed to full hp after every encounter. Pathfinder replaced this with Stabilize, which will stabilize a character at negative hp, but not cure damage. But CLW will only be DC 12.

Clerics do not need to add the spell to their spellbook, so a good enough roll permits any spell at L1 (and a bad roll KOs them so they need to rest for a while).

How do spontaneous spellcasters work under this model? They don't seem to get more access to spells.

 

[Yanko128]

Maybe a better option would be to divorce spellcasting from skills, and have it as an alternate Spellcasting Attack Bonus. This would follow the same pattern as basic attack bonus. Of course you would need +X wands and other implements that would be used in place of weapons. This might even help fighters, as it would make them partial casters.

 

[Dandu]

Unlimited castings also changes the ground rules. Dandu refers to Cure Minor Wounds, which at 0 level appears to have a 10 DC and less than 1d4 nonlethal as a penalty for failure. It should quickly be autosuccess, so out of combat, everyone will be healed to full hp after every encounter.

What's even more fun is that cure spells remove nonlethal damage as well as lethal damage, which means there is effectively no penalty for failing a spellcraft check out of combat.

 

[rgard]

d20 Sovereign Stone and the d20 Thieves' World games both had a skill based spell casting system. IIRC, each spell had a success roll amount (skill check on spell craft) and if the caster came up short he or she could continue to try cast the spell the following round adding the next roll to the previous roll and so on.

I may have got some of that wrong, but I think that is the gist of the system.

 

[Greenfield]

Call me a cynic, but to me this looks like a simple skill penalty on casters. They have to dedicate skill points to Spellcraft every level to stay in business. They also have to expend feats for Skill Focus and, when available, Greater Skill Focus.

And in return, Wizards become gods.

Int is the score that gives skill points, and Spellcraft is an Int based skill. It's also the casting stat for Wizards (and almost nobody else).

The Sorcerer class goes away, period. No reason to ever run one, mechanically speaking. The difference between a Sorcerer and a Wiz was Charisma based casting (a penalty under this system), more spell slots per level (meaningless under this system), countered by access to a smaller number of spells they can actually cast. (I presume that, since you mentioned spell books, this limit would remain?)

My build under this system would be a Human with Able Learner. He'd end up as Wiz 1/Cleric 1/Ranger ???

Since he could maintain his Spellcraft, maximized, and still have plenty of skill points left, he'd always be ready with any spell, Arcane or Divine, be near full BAB and have decent hit points. There would be very little reason for him to ever take any additional levels in Wiz or Cleric.

So let's see... Start him with an Int of 14 or 16, both for skills and Spellcraft bonus.

He'll max Spellcraft at 1st level (4 ranks), take Skill Focus (Plus 3 to the roll), and have his Int bonus (another 3) for +10 at 1st level. Unlimited 1st level spells, jut don't roll a 1.

Oh, and since Cure Light *does* heal both lethal and non-lethal damage, as soon as he gets his Cleric level the non-lethal damage becomes meaningless. He can cure a D8 of it 100% of the time, any time he likes. (His Spellcraft will be +11 at 2nd level.)

Would he, as a 1st level Ranger (when that happens) get access to spells like Entangle immediately? It's 1st level for that class, so he'll have it 100% of the time, no failure possible. And 2nd level spells of any class or school are now in the "Don't roll a 1" category.

5th level spells like Raise Dead are theoretically available as soon as he gets his Cleric level, of course (he needs to roll an 18 to get the DC 28, but he can try over and over until he gets it, he just has to cast a lot of Cure Light in between to recover from the failures. )

To throw a big-boom like Fireball or Lightning Bolt he'd have to roll a 6 or better. Can only "fail by 5 or more" on a natural 1. Really good odds.

And I'm hardly trying. I know there are ways to make this build look like a total piker.

So, depending on the players, I can see how they'd like this system. It can be seriously exploited by anyone with even a hint of rules savvy.

Sorry to rain on your parade.

 

[doghead]

Sorry to rain on your parade.

It might not be what he was hoping to hear.

But it is a really clear outline of some of the likely outcomes if he chooses to implement the change, thus allowing the OP to make a more informed decision. Which is a good thing.

thotd