Why is damage reduction an extraordinary ability for barbarians and a supernatural abilty for the creatures in the MM?
Is there a reason why I shouldn't treat a dragons DR as an extraodinary abilty (i.e. uneffected by an antimagic feild)?
Why is damage reduction an extraordinary ability for barbarians and a supernatural abilty for the creatures in the MM?
Is there a reason why I shouldn't treat a dragons DR as an extraodinary abilty (i.e. uneffected by an antimagic feild)?
Get out of my mind!!!
I do this already as a house rule. There is a bit of work to do in the decision making process as to which critters are affected. I haven't developed a methodology any better than common sense up until this point; however, it seems pretty straight forward.
A stone golem or an earth elemental will not suddenly become as easy to cut as flesh when inside an antimagic field (not that you could get an elemental into one but you know what I mean). On the other hand, it is easier to see why a creature like a vampire or rakshasa would have damage reduction as a supernatural ability.
That's my two coppers (Steve, I'm stealing your saying - sorry).
Cheers,
C.
Why is damage reduction an extraordinary ability for barbarians and a supernatural abilty for the creatures in the MM?
Is there a reason why I shouldn't treat a dragons DR as an extraodinary abilty (i.e. uneffected by an antimagic feild)?
Well a supernatural ability is defined as a magical power. Barbarians do not normally use magic innately, at least not without obtaining a spell casting / magic-innate class or prestige class.
Dragons and the other monsters with damage reduction (Su) are all beings of magic in some way (they might not have the magic animal subtype, but any subtype other than humanoid, animal, and plant I believe are magic in nature).
The reason that BBN DR is EX is because of the mentality of a BBN. Wounds just don't affect a BBN like it would a FTR. Now a dragon's DR is because it is a magical creature. It's innate magical nature allows it to become more resistant to physical damage. I'd suggest reading the Draconimicon for further explanations.
This is partially addressed in the Monster Manual errata file. Here's the quote:
Damage Reduction
Damage Reduction is either extraordinary (Ex) or
supernatural (Su). Use the following guidelines if it
is not specified.• DR X/slashing, piercing, or bludgeoning
should be (Ex)
• DR X/adamantine should be (Ex)
• DR X/-- should be (Ex)
• DR X/silver or cold iron should be (Su)
• DR X/magic should be (Su)
• DR X/chaotic, lawful, holy, or unholy
should be (Su)
So, that really doesn't quite answer the original question, but if you look you can sort of extrapolate it. As others have said, the Ex versions of DR (including the barbarian's) are all raw physical properties. The Su types are all magical in nature.