Does a warlock ever need more than 27 Use Magic Device?

Question

Is there any benefit to a Use Magic Device modifier over 27 for a Warlock? It seems like the maximum check you would ever need is to cast a level 9 spell from a scroll, which is 20+17. Am I missing anything, or is that the hard cap to the skill (since I don't care about deciphering someone's spellbook)? For example, let's say there is some scroll that you must be evil to cast, and I'm chaotic neutral, and it's a level 9 spell -- the alignment check seems to become unimportant because the check to cast the level 9 spell is higher (30 vs 37). Since I can just take 10, then if I have a 27 modifier, that's pretty much endgame for UMD. Am I missing anything?

It seems like it would be more fair if the difficulties somehow combined, but that doesn't appear to be the case. Because of that, I just wanted to make absolutely sure I wasn't missing something.

(warlocks can take 10 on use magic device after level 4)

Answer 1

There may be several reasons to pump your Use Magic Device higher:

• Your UMD (or, indeed, any) skill may be decreased by conditions such as Shaken, Sickened, Energy Drained or Charisma Damage. Which would make you roll on the check which you previously could succeed effortlessly. So if you rely on being able to always make that 37 UMD check, you might want a small buffer to accommodate penalties.

• Spell scrolls do not have to be the minimum caster level for that spell (the randomly generated ones are, however). If you are commissioning a scroll from a wizard or cleric, they can make it as high as their CL. And there are very good reasons to commission (and cast) a scroll of, for example, CL20 Magic Vestment or CL30 Holy Word, if you can find a caster that powerful.

Answer 2

A Use Magic Device skill modifier of +27 (therefore, for a warlock, assuring a result of 37) is likely high enough for most purposes. It's only if a warlock must emulate a very high-level class feature that an even higher result becomes desirable. That is, the Use Magic Device skill use Emulate a Class Feature says

Sometimes you need to use a class feature to activate a magic item. In this case, your effective level in the emulated class equals your Use Magic Device check result minus 20. For example, Lidda finds a magic chalice that turns regular water into holy water when a cleric or an experienced paladin channels positive energy into it as if turning undead. She attempts to activate the item by emulating the cleric’s undead turning ability. Her effective cleric level is her check result minus 20. Since a cleric can turn undead at 1st level, she needs a Use Magic Device check result of 21 or higher to succeed. (Player's Handbook 86)

With a guaranteed result of 37, this means emulating level 17 class features automatically, but to emulate even high-level class features will require a roll. Although I am unaware of, for example, a magic item that only work for a monk that possesses the class feature perfect self, were one to exist, a warlock with only a Use Magic Device modifier of +27 must roll to make that magic item work.

Answer 3

Realistically, a +10 bonus is the highest one you’re really likely to want. That allows you to take-10 to hit the DC 20 check for using a magic wand. Scrolls are far, far less efficient than wands, which means a warlock heavily focusing in magic items (which is a good idea) should be focusing in wands.

That said, supposing you want to use scrolls you come across in your travels, then no, +27 is not necessarily sufficient. In fact, there is no number that is necessarily guaranteed to work. The caster level of a scroll need not be the minimum for the scroll level, and even in a non-epic campaign, caster level 20th is not a limit. Even in core, just off the top of my head we could have a scroll made while under the effects of an orange ioun stone and prayer bead of karma for caster level 25th. With supplements, that number can get arbitrarily high—that is, no matter how high your UMD check is, it will always be possible for someone to have a higher caster level than you can hit.

So after +10, you start to get much less utility from UMD bonuses, and after +27, you are really looking at a very limited subset of magical items that you cannot use, but there still can be some that you can’t.

Answer 4

I found a Q&A by Rich Baker (archived here) in which he states you cannot use the warlock ability Deceive Item when crafting. As such, if you want to craft an item that requires a level 9 divine spell, you need to roll a DC 25 + spell level check. So you need at least a 33 UMD in order to be able to always hit a DC 34 target.

So, Warlock max UMD is therefore +33 unless you do not want to craft items, in which case it is +30 for use of caster level 20 items on a take 10 deceive item roll.