Spell Penetration vs Spell Focus

[VKhaun]

Hi, noob here, I have a friend telling me to always get spell penetration first and foremost because it's a larger benefit to the same thing, but they are worded so differently. It makes me think Spell Focus makes it tougher for enemies to make those saving throw drawbacks like 'damage is cut in half on a succesful reflex save' it would make the reflex save tougher on the mob, vs Spell Penetration making landing the spell in the first place easier on me.

Could someone explain the trade off to me a little better?


Unrelated: Are the Iron/Steel/Mithril/Adamantine Companions worth taking?

[rimble]

Hi, noob here, I have a friend telling me to always get spell penetration first and foremost because it's a larger benefit to the same thing, but they are worded so differently. It makes me think Spell Focus makes it tougher for enemies to make those saving throw drawbacks like 'damage is cut in half on a succesful reflex save' it would make the reflex save tougher on the mob,

Yep, that's exactly right.

vs Spell Penetration making landing the spell in the first place easier on me.

Spell Penetration helps you overcome Spell Resistance. Most, if not all, higher level creatures (and they'll start showing up more as you reach Gianthold and then beyond) have a Spell Resistance score. Most non-damaging spells need to bypass their Spell Resistance to work, and then they get their Saving Throws to boot! The enemy Spell Resistance gets pretty high, I'd say most casters take both Spell Penetration Feats and at least two Spell Penetration Enhancements. Don't take them early though, when you start seeing these glowy blue shields pop up on your enemies, that means you bounced off their Spell Resistance.

I had a good ol' time leveling up my Sorcerer with both Enchantment Spell Focus Feats...but when the time came they got tossed for both Spell Penetration Feats...

Unrelated: Are the Iron/Steel/Mithril/Adamantine Companions worth taking?

Not really.

[Arianrhod]

To say the same thing in reverse - at lower levels (under 8th), Spell Penetration does next to nothing for you. The only low level creatures with spell resistance are drow. At mid levels, you can add Flesh Renders and Duergar (not sure aout the Duergar). It's not until you start fighting large numbers of demons & devils that spell resistance becomes much of a factor. At lower levels, you want to raise your spell save DCs (by having a high caster stat, using spell focus items, etc.). Raising your spell penetration can wait till it actually has some spell resistance to penetrate.