Level checks for Arcane Spell Failure?

[JimAde]

Either approach is certainly valid.

You know, I wrote a really long post going over some numbers, but I talked myself into a corner

That feat you mentioned sounds really gonzo. I'd like to see the source if you can find it.

I think it's OK that this rewards dedicated casters. Most of the fighter/caster prestige classes let you advance your caster level (usually at half rate) so that would probably be the way to go for such a character. You'll have to look to make sure Spellcraft is a class skill for those classes, too (I'm sure it usually is).

I do have one problem with using the AC bonus of the armor: what about mithral and similar enhancements that make armor lighter? The ASF takes that into account, so you should remember to do so, too. Also, I assume you mean the AC bonus of the base armor, and won't penalize people for having enhanced armor.

Should work with either approach. Unfortunately there are no arcane spellcasters in my current group to try it out. They have an NPC Paladin/Wizard with them so I think I'll use my method with him.

 

[DanMcS]

I've been kicking around the idea of using a level check instead of the flat ASF chance. I don't like the idea that you have as much trouble casting a spell you've known for years as you do with one you just picked up. Plus the current rules violate the "Roll high on a d20 to succeed" thing.

No they don't, you just need to set it up right. If the spell failure chance is 15%, then the DC is 4 on a chance check (flat d20, no modifiers) to cast the spell normally. Perfectly "roll high on a d20 to succeed", and action-pointable to boot.

 

[JimAde]

No they don't, you just need to set it up right. If the spell failure chance is 15%, then the DC is 4 on a chance check (flat d20, no modifiers) to cast the spell normally. Perfectly "roll high on a d20 to succeed", and action-pointable to boot.

Yep, that was my first thought. And as soon as I thought it I thought, "That's all well and good, but why should I fail on my 1st level spells the same as my 3rd level? Characters get better at everything else as they progress, why not this?"

Good point about the Action Points, though. That one change would make a huge difference in a campaign that uses APs. Maybe that's why the RAW aren't done that way.

 

[Hawken]

I believe that feat is out of The Complete Divine and allows a multi-classed character to add a maximum of four non-caster levels to his/her casting class for level dependent effects (but not spells per day).

If it is limited to 4 non-caster levels, that should be fine. It would provide a bonus to level checks similar to Skill Focus (Spellcraft) using the skill point method. But if the bonus actually is more than 4 levels, then it would be too much.

I do have one problem with using the AC bonus of the armor: what about mithral and similar enhancements that make armor lighter? The ASF takes that into account, so you should remember to do so, too. Also, I assume you mean the AC bonus of the base armor, and won't penalize people for having enhanced armor.

Yes, I had meant the base AC bonus of the armor and would not include enhancement bonuses to penalize the check. I think mithril reduces Arcane Caster percentage by 15%, so I'd just reduce the DC of casting in mithril armor by 3, and maybe increase it by 3 for armor that is made of heavier materials. Magical enhancements that reduce the arcane caster penalty, would similarly reduce the DC by 1 point per 5% points reduced.

 

[JimAde]

If it is limited to 4 non-caster levels, that should be fine. It would provide a bonus to level checks similar to Skill Focus (Spellcraft) using the skill point method. But if the bonus actually is more than 4 levels, then it would be too much.


Yes, I had meant the base AC bonus of the armor and would not include enhancement bonuses to penalize the check. I think mithril reduces Arcane Caster percentage by 15%, so I'd just reduce the DC of casting in mithril armor by 3, and maybe increase it by 3 for armor that is made of heavier materials. Magical enhancements that reduce the arcane caster penalty, would similarly reduce the DC by 1 point per 5% points reduced.

Sounds right. That Complete Divine feat sounds spiffy. I assume you can't take it multiple times.

Hawken, if you get a chance to play-test this I'd love to hear about it. I'm going to try out my method with my NPC this week-end and see how it goes. I'm going to throw the group into a fight right away so we'll see...

 

[DanMcS]

Good point about the Action Points, though. That one change would make a huge difference in a campaign that uses APs. Maybe that's why the RAW aren't done that way.

I don't think so, since Action Points weren't a twinkle in someone's eyes when they made up the rules for spell failure, missing someone partially concealed, and stabilizing under 0 hps (the other rules I can think of offhand that uses a flat percentage chance).

I'd expect that if the system included APs at its base, those kinds of things would be referred to as something like a chance check, with a target number on a d20, specifically so they would be action-point-able.

It doesn't make that huge of a difference in the campaign (I've been playing an armored fighter/sorceror), because you're blowing action points just to succeed at spellcasting; other wizards can do it with no chance of failure, while the other fighters are using them to hit, and the skilled types are using them for skills.

 

[Merlion]

Sounds like a fine idea to me.

Course if it was me, I'd remove ASF entirely...or at least for anything but the heaviest armors.

Or conversly, I'd make it apply to Divine spells too.

 

[Spatzimaus]

The thing that gets me is, what exactly is ASF supposed to represent? No matter what your answer is, there seems to be a better way within the rules already.
If it's a matter of armor interfering with your ability to gesture (as evidenced by the ability to use non-somatic spells just fine), why isn't it just a Concentration check with the armor check penalty applying?
If it's the armor blocking mystical energy or something, shouldn't material have more of an impact on it?
In both cases, shouldn't divine casters suffer as well?

Frankly, to me this is just one of the MANY parts of D&D that you just write off as an artifact of the old rules; yes, I know it's a new mechanism, but it's intended to maintain the old "wizards don't wear armor but clerics do" status quo, in a way that doesn't allow you to use +skill items to trivialize the check.

Which, of course, is why in my friends' homebrew we ditched the whole thing. In a skill-based magic system you can apply Armor Check Penalties to all sorts of things. For instance, we have one skill (Focus) to replace Caster Level in spell effects, and it's affected by Armor Check Penalty. So, casting in armor results in a less powerful spell, no matter how skilled you are.