UMD for a staff

[Frosty]

Okay, so let's say I have a cleric wanting to use UMD to activate a Staff of Evocation (http://www.d20pfsrd.com/magic-items/staves/staff-of-evocation/) and use Fireball (which is not on the Cleric spell list).

So, according to the text of UMD...Use a Wand, Staff, or Other Spell Trigger Item: Normally, to use a wand, you must have the wand’s spell on your class spell list. This use of the skill allows you to use a wand as if you had a particular spell on your class spell list.*Failing the roll does not expend a charge.

That's fine, the cleric makes the DC20 to pretends to have Fireball on his spell list. He casts Fireball from the staff, spending one charge. But...what is the caster level and save DC of this Fireball? Staff rules says that you use your own CL and save DC, but the Cleric has no arcane caster level. Does he just use the CL of the staff itself (which is 13 in this case), or does he use his own cleric CL? Regarding the save DC, does the cleric use Wisdom for the Fireball as though casting a divine spell, or does he need to use some other stat? If some other stat, should it be Int or Cha (or maybe the Cleric gets to pick)?

[Crake]

The staff doesn't have an arcane or divine caster level, and doesn't care about whether the cleric is arcane or divine, or whether his main casting ability is int, wis or cha. A cleric with the fire domain would normally be able to freely activate a staff of evocation (at least to use a fireball) using all the standard rules, so UMDing the staff to make it think fireball is on your list simply skips the need to have the spell on your list, but otherwise uses all the standard rules. That is: 13 or your CL, whichever is higher, and minimum DC, or your spell DC, whichever is higher.

[Frosty]

Thanks! Staves are...exceptionally powerful it seems.

[Nibbens]

Thanks! Staves are...exceptionally powerful it seems.

IMO, Thats the reason they only have 10 charges. LOL.