Magic Item Help

[Rolzup]

I like making unique magic items. Far more interesting, in my opinion, than the standard stuff...and besides, it's fun. Being relatively new to 3.5, though, I find myself with a question or two.

This particular item is actually two separate things: a sword and a ring.

The ring is the simpler of the two. It's a Ring of Major Fire Resistance that also marks the wearer as the proper wielder of the sword. In appearance, it's a simple ring of obsidian, unadorned and uncarved.

The sword, on the other hand.... It's called Blackflame, or the equivalent in Giantish. It's a +3 Keen Greatsword, with an obsidian blade (being magical, it's not as brittle as obsidian normally would be). Additionally, it's got a couple of extra powers....

If the wearer of the ring calls to it, Blackflame will leap into his hand. Grants the equivalent of the Quickdraw feat, as long as the sword is anywhere in the same room.

The blade will change its size to match that of the wearer of the ring.

(This used to be standard, back in the old days. Is it still the case, or is it only armor and rings that do this sort of thing?)

Finally, once (?) per day the wielder of the sword can call out a command word as he swings it ("Burn!" in Giantish). If the sword hits, the target must immediately take a fortitude save. If he fails, his blood begins to boil.... 6d6 damage, and the subject is at -2 to attacks, AC, and skill checks until the effect wears off. If the save is made, the subject takes half damage but suffers no other ill effects.

The plan is for this weapon to fall into the hands of an experienced party, 12th level or so. Of course, it'll be used against them by an angry Fire Giant chieftain first, but them's the breaks.

My question is, what should I set the DC of the Fortitude save at? Is there a guideline as to how high they should be set, depending on the level of the campaign? I don't want the blood boiling to be overwhelming, but nor do I want it to be entirely useless. Perhaps make the DC equal to the damage that the sword inflicts on the turn that it hits?

Judging by what a fighter with Power Attack and a +3 Keen Greatsword can do, of course, that might easily be an appallingly high number....

Rolzup

 

[Steve Jung]

/snip/The blade will change its size to match that of the wearer of the ring.

(This used to be standard, back in the old days. Is it still the case, or is it only armor and rings that do this sort of thing?)

In 3.0, magical armor, clothing, and jewelry could resize (DMG 3.0, page 176). In 3.5, armor has fixed sizes (DMG 3.5, page 213).

/snip/
My question is, what should I set the DC of the Fortitude save at? Is there a guideline as to how high they should be set, depending on the level of the campaign? I don't want the blood boiling to be overwhelming, but nor do I want it to be entirely useless. Perhaps make the DC equal to the damage that the sword inflicts on the turn that it hits?
/snip/
Rolzup

For a saving throw against a spell or spell-like effect from a magic item, the DC is 10 + the level of the spell or effect + the ability modifier of the minimum ability needed to cast that level of spell.

So you need to figure out what spell the power represents.
For example, if you choose fireball as the basis:
DC = 10 + 3 (fireball's level) + 1 (ability modifier for Int/Cha 13, the minimum to cast third-level spells) = 14