[3.5] ACs of Common Magic Items

[Duke of Urrel]

According to the SRD, "A carried or worn object’s AC is equal to 10 + its size modifier + the Dexterity modifier of the carrying or wearing character."

So if a player wants to sunder an enemy's magic item, all the DM has to know besides the player's stats is the item's size modifier.

Alas, the Armor Class of a magic item is a mystery in some cases. According to the SRD, the commonest types of magic items – excluding magic arms and armor – have the following ACs:

potion: AC 13
ring: AC 13
rod: AC 9
scroll: AC 9
staff: AC 7
wand: AC 7

I can analyze the ACs of potions, rings, and scrolls easily enough. Both potions and rings are Fine-sized objects, and their Dexterity modifier is –5 when they are unattended, so 10 –5 +8 =13. Magic scrolls are Diminutive in size, so their AC is 10 –5 +4 =9.

Confusingly, by the same math, a magic rod should be Diminutive, just like a scroll, and magic staffs and wands should both be Tiny-sized objects. This doesn't correspond to the size categories of these items as they are described in the SRD. To review:

Rods are 2 to 3 feet long and should be Small-sized.

Staffs are 4 to 7 feet long and should be Medium-sized.

Wands are 6 to 12 inches long and should be Diminutive in size.

Correspondingly, unattended magic rods should have an AC of 6 (not 9), unattended magic staffs should have an AC of 5 (not 7), and unattended magic wands should have an AC of 9 (not 7).

I've tried to understand why these items have the ACs they are given in the SRD. Maybe magic rods add a +3 deflection bonus to their AC, and maybe magic staffs add a reduced deflection bonus of +2. But it doesn't make sense that a magic wand's AC is only 7 rather than 9, unless all wands are somehow cursed...

Am I missing something obvious here? I appeal to the sages of the Playground for counsel!

[TuggyNE]

Hmm. I think the AC of a wand is either a) legacy-based fiat or b) an error caused by using the modifier for Tiny instead.

Rods and staffs might have some sort of fiated natural armor bonus or something.

I really don't know why the numbers are so thoroughly off, though!

[Duke of Urrel]

Hmm. I think the AC of a wand is either a) legacy-based fiat or b) an error caused by using the modifier for Tiny instead.

Rods and staffs might have some sort of fiated natural armor bonus or something.

I really don't know why the numbers are so thoroughly off, though!

Yes, and I wonder if I shouldn't just ignore those unexplained ACs. Unless somebody comes up with an explanation for them, that's what I feel inclined to do.

I do like the Sunder action, because it gives weapon wielders some advantage over users of magic items at close range. It's a small compensation for the many advantages that magic has over most mundane powers.

On the other hand, I don't want to make it too easy to destroy a magic rod or staff, so if there's a description somewhere that explains the ACs given for these items in the SRD, I'll go along with it. As for magic wands, I agree with you that the writers of the rulebooks seem to have made a plain mistake. A wand's AC when unattended really should be 9, not 7.