Use Magic Device

[kjenks]

Emphasis mine.

Huh? How does the word "need" imply in any way that you can't emulate the class feature of caster level while activating a staff? Are you trying to say that you can't emulate that class feature unless you need to, and therefore you can't emulate that class feature unless you need to?

 

[Kurotowa]

Emulate class feature.

This one's been gone over a lot by Warlock fans, so let me lay out my take on it from that.

Caster level is a not a class feature. Class features are the bold entries in the Class Features sections of a class. The relevant class feature in this situation is Spells. Now here's the tricky part. Most Spells class features do not mention caster level. In fact caster level isn't defined until the Magic chapter, which says "A spell’s power often depends on its caster level, which for most spellcasting characters is equal to your class level in the class you’re using to cast the spell."

Sadly, this still isn't 100% clear. One line of thought is that the level you emulate Spells at doesn't matter, because what's being checked is your level and not the level you have the feature at, and thus with UMD you have a caster level equal to your character level. The other line of thought is that Spells does directly set caster level, and you have a caster level equal to your UMD check minus 20. So far I know of no real resolution.

 

[jeffhartsell]

I'm still not seeing what you're talking about, Hypersmurf. Why can't you emulate an ability score when activating a staff? Because the example and the text in parenthesis discuss scrolls?

A wizard with an INT of 10 can still use a staff that contains any arcane spell on the wizard list. The save DC would be the spell level + 0 Int bonus.

The UMD check to activate a staff DOES NOT include additional checks to emulate an ability score or caster level.

Staff Descriptions
Staffs use the wielder’s ability score and relevant feats to set the DC for saves against their spells. Unlike with other sorts of magic items, the wielder can use his caster level when activating the power of a staff if it’s higher than the caster level of the staff.

Note that staves use the wielder's ability score. UMD allows you to emulate an ability score when it is required to activate the item. The ONLY magic items that require an ability score to activate them are scrolls.

Also note that the caster level of a staff is your caster level or that of the staff, whichever is higher. Since you don't have a caster level with the relevant spell (most likely), you use the staff's caster level. Since you don't need a caster level to activate the staff, you cannot emulate a caster level.

If staves required those a la scrolls then you could emulate them.

 

[Hypersmurf]

Also note that the caster level of a staff is your caster level or that of the staff, whichever is higher. Since you don't have a caster level with the relevant spell (most likely), you use the staff's caster level.

Now, there's an interesting point here when UMD is used by a caster.

Let's say we have a 18th level Cleric with the Fire Domain and a Staff of Fire. The staff has a CL of 8.

The cleric wishes to activate Burning Hands from the staff. The spell is on his class spell list, so he uses his own caster level - 18 - and his own Wis modifier to set the DC.

Now he wishes to activate Fireball. It's not on his class spell list, so he can't just use the Spell Trigger action. Instead, he uses UMD, which allows him to activate the spell as if it were on his class spell list. When he activates a spell on his own class spell list, he uses his own caster level and his own Wis modifier.

So, is it a CL 8 fireball, or a CL 18? Does he use his Wis modifier, his Int modifier, or his CHa modifier?

He's activating it as if it were on his class spell list. As far as I can tell, it's CL18 and Wis.

On the other hand, "Use a Scroll" uses the same wording - as if it were on your list - but "Emulate an ability score" refers to "the class you're emulating when you try to cast the spell from the scroll".

-Hyp.

 

[jeffhartsell]

Now, there's an interesting point here when UMD is used by a caster.

<snip>

Now he wishes to activate Fireball. It's not on his class spell list, so he can't just use the Spell Trigger action. Instead, he uses UMD, which allows him to activate the spell as if it were on his class spell list. When he activates a spell on his own class spell list, he uses his own caster level and his own Wis modifier.

So, is it a CL 8 fireball, or a CL 18? Does he use his Wis modifier, his Int modifier, or his CHa modifier?

He's activating it as if it were on his class spell list. As far as I can tell, it's CL18 and Wis.

On the other hand, "Use a Scroll" uses the same wording - as if it were on your list - but "Emulate an ability score" refers to "the class you're emulating when you try to cast the spell from the scroll".

-Hyp.

That question has come up with our group as well. Scrolls are either arcane or divine based on who created them and use the relevant stat. Techincally if a cleric with the fire domain cast an arcane burning hands from a scroll created by a wizard he'd need to use INT even though he has burning hands on his list.

Staves don't have the same issues and as far as we can tell you use your caster stat and caster level for staves as long as you have the spell on your list, and UMD emulates that feature. Thus, in the above example, the cleric would have caster level 18 and use his WIS.

Side comment: for scrolls we house rule that as long as you have the spell on your spell list, you use your casting stat to determine if you can cast it.

To have any chance of activating a scroll spell, the scroll user must meet the following requirements.

- The spell must be of the correct type (arcane or divine). Arcane spellcasters (wizards, sorcerers, and bards) can only use scrolls containing arcane spells, and divine spellcasters (clerics, druids, paladins, and rangers) can only use scrolls containing divine spells. (The type of scroll a character creates is also determined by his or her class.)
- The user must have the spell on his or her class list.
- The user must have the requisite ability score.

If the user meets all the requirements noted above, and her caster level is at least equal to the spell’s caster level, she can automatically activate the spell without a check. If she meets all three requirements but her own caster level is lower than the scroll spell’s caster level, then she has to make a caster level check (DC = scroll’s caster level + 1) to cast the spell successfully. If she fails, she must make a DC 5 Wisdom check to avoid a mishap (see Scroll Mishaps, below). A natural roll of 1 always fails, whatever the modifiers.

 

[Hypersmurf]

Staves don't have the same issues and as far as we can tell you use your caster stat and caster level for staves as long as you have the spell on your list, and UMD emulates that feature. Thus, in the above example, the cleric would have caster level 18 and use his WIS.

So a pure Rogue who activates a staff will always use the minimum save DC, despite having Wis, Int, and Cha of 22 each, because none of those are the ability score that sets the DC for a Rogue's spells, right?

-Hyp.

 

[jeffhartsell]

So a pure Rogue who activates a staff will always use the minimum save DC, despite having Wis, Int, and Cha of 22 each, because none of those are the ability score that sets the DC for a Rogue's spells, right?

-Hyp.

That is a tricky one. But yes, we rule that a non-caster uses the minimum caster level and save DC of the staff.