Mithral armor and Arcane spell failure

[galahad2112]

Or really, What does the phrase "other limitations" mean with regards to casters that ignore ASF in light armor? The relevant text:

special materials, mithral wrote:

Most mithral armors are one category lighter than normal for purposes of movement and other limitations. Heavy armors are treated as medium, and medium armors are treated as light, but light armors are still treated as light. This decrease does not apply to proficiency in wearing the armor.

Does a bard wearing mithral breastplate ignore the ASF? Or just have it reduced by 10%?

[Jiggy]

A bard in a mithral breastplate is wearing light armor and suffers no ASF. On the other hand, he's not proficient (still needs medium proficiency) and therefore takes the ACP (in this case, -1) on attack rolls.

Unless of course he has the Armor Expert trait. ;)

[Sniggevert]

It counts as light armor, so a bard would suffer no ASF for wearing a mithral breastplate.

[galahad2112]

Cool, that's what I had originally thought, but I've been wrong before.

Also, via extension of this rule, a 7th level magus could wear mithral full plate and cast without ASF, correct? He'll still take the ACP, which is much heftier than the bard in the breastplate, but for casting purposes, it's legit, right?

[Sniggevert]

galahad2112 wrote:

Cool, that's what I had originally thought, but I've been wrong before.

Also, via extension of this rule, a 7th level magus could wear mithral full plate and cast without ASF, correct? He'll still take the ACP, which is much heftier than the bard in the breastplate, but for casting purposes, it's legit, right?

Yes. However, as Jiggy pointed out the ACP is not just taken into account on skills if you're not proficient. It'll penalize his attacks as well. This could be more of an issue for said magus, though it would still be legit to use the mithral full plate.

[galahad2112]

Oh, absolutely, the ACP is a steep penalty for attack rolls. Not trying to get around that. Just the ASF.

Also, thank you very much for the quick responses!