Do I have this right?

[Leyoni]

Need to understand Difficulty Class. As I understand it DC is 10 + spell level + CHA modifier - monster CR.

Is that right?

With a 30 CHA (will go to 36 with L16 stat increase, +3 tome, and +6 item) do I need more?

I'm figuring I can get additional CHA boost from greensteel. But, by the time I get around to that I will have done pretty much everything without the extra CHA anyway.

Also, should I grab Spell Penetration & Greater Spell Penetration? Had not planned for them originally but can swap for them.

Thx.

[Freeman]

The monster's CR has nothing to do with it. The DC is 10 + Spell Level + Charisma Modifier + feats(Spell Focus, Greater Spell Focus) + items(Such as Dreamspitter, Napkin, etc). The monster then makes a saving through versus that DC, just like you have to save versus enemy spells. For a sorc, 32-34 should be good at level 16. You may want to pick up the Spell Penetration feats and items though, since SR is a real pain in the endgame content.

[Kistilan]

Hey Leyoni-

Yeah, I'm no expert, but your math looked about right. I'm sure someone will disagree or confirm my assertion on that.

EDIT: Just realized you placed a minus CR. The only thing CR does is add to the constitution (& fortitude bonus) of a monster, thus making spells that require a fort save fail to take effect on the target easier to resist if the monster has more constitution. Rule of thumb is, if it has a lot of hit points, use a will save spell against it. If it doesn't have a lot of hit points and just has a high armor class, use a fort save spell against it. If it has lots of hit points and lots of will (doesn't accept will spell effects or is immune), then go direct damage. If it EVADES your lightning or fireballs, use touch-based or auto-hit evocation spells (force missile, shocking grasp, chill touch, magic missile, etc).

As far as increasing your DC further, get scepters/clubs of the schools you want to cast. Enchant, Necromancy, Illusion, Evocation & Transmutation are VERY helpful at higher levels and increase your DC by +1 (or +2 if you get the right item) -- mostly raid or rare loots.

I highly recommend getting Spell Pentration at least & buying up the enhancement line. If you've found you don't need to buy anything else at a later feat, pick up Greater Spell Penetration too. If you can't get through the spell resistance, even a High DC won't help you because the spell never "attempts to affect" the target due to the spell resistance shrugging the spell off.

[Merkinsal]

Spell Penetration = [d20 + Caster Level + feats + enhancements + item] = Spell Resistance.

Spell DC = [10 + Spell Level + CHA mod + feats + items] (no enhancements for Spell DC) > d20 + save


Cha mod is the difference over 10 divided by 2 as you know. The feat Heighten plays a big part here by increasing the spell level of any spell to the highest level you can cast.

The feats Spell Pen and Greater Spell Pen add 2 apiece for +4 and three enhancements for another +3.

I have both spell pen feats but there are some out there with only one. Actually to be more accurate, I know of one sorc who posts on this forum who "says" he only has one. :) However, he is a very wise sorc too, and I think he might be pulling our legs :D

[Leyoni]

Thanks all for the correction to my thinking. No minus for CR. Good info.

I didn't take spell penetration at all as I was thinking I wouldn't need them. Can see I was wrong (that's what happens when you follow a build templet -- fortunately nothing that can't be fixed). Will make the adjustments.

Thanks again.

[ArkoHighStar]

Thanks all for the correction to my thinking. No minus for CR. Good info.

I didn't take spell penetration at all as I was thinking I wouldn't need them. Can see I was wrong (that's what happens when you follow a build templet -- fortunately nothing that can't be fixed). Will make the adjustments.

Thanks again.

spell pen has only really been an issue with mod 6 and 7 as many of the mobs have very high spell resistance, and are resistant to much of the direct damage spells like firewall and fireball etc that were very popular in mod 4 and 5

[Leyoni]

Well that makes sense. I haven't needed them thus far so thought I was doing alright. I can fix that tho as I get ready for Tor, Reaver and Vale.