What is the multiclassing xp penalties?!?!?!

[socball22]

So I'm playing a Sorcerer 5/Sand Shaper 5 (Sandstorm) and plan on continuing Sandshaper till 10 and then I don't know what after that. BUT the real concern is that I want to take a one level dip into Spellthief and then take the Master Spellthief at level 12 because that would give me 10 levels of Steal Spell. I've looked everywhere and I can't find the exact penalty for taking one level dip. Is it something that fluctuates with each level? or does the DM decide? or how does this work?

[Callin]

PHB1

XP FOR MULTICLASS CHARACTERS
Developing and maintaining skills and abilities in more than one
class is a demanding process. Depending on the character’s class
levels and race, he or she might or might not suffer an XP penalty.
Even Levels: If your multiclass character’s classes are nearly the
same level (all within one class level of each other), then he or she
can balance the needs of the multiple classes without penalty. For
instance, a 4th-level wizard/3rd-level rogue takes no penalty, nor
does a 2nd-level fighter/2nd-level wizard/3rd-level rogue.
Uneven Levels: If any two of your multiclass character’s classes
are two or more levels apart, the strain of developing and
maintaining different skills at different levels takes its toll. Your
multiclass character suffers a –20% penalty to XP for each class that
is not within one level of his or her highest-level class. These
penalties apply from the moment the character adds a class or raises
a class’s level too high. For instance, a 4th-level wizard/3rd-level
rogue gets no penalty, but if that character raises his wizard level to
5th, then he takes the –20% penalty from that point on until his
levels were nearly even again.
Races and Multiclass XP: A favored class (see the individual
race entries in Chapter 2: Races) does not count against the character
for purposes of the –20% penalty to XP. In such cases, calculate
the XP penalty as if the character did not have that class. For
instance, Bergwin is an 11th-level gnome character (a 9th-level
rogue/2nd-level bard). He takes no penalty to his XP because he has
only one nonfavored class. (Bard is favored for gnomes.) Suppose he
then attains 12th level and adds 1st level as fighter to his classes,
becoming a 9th-level rogue/2nd-level illusionist/1st-level fighter.
He then takes a –20% XP penalty on future XP he earns because his
fighter level is so much lower than his rogue level. Were he awarded
1,200 XP for an adventure, he would receive only 80% of that
amount, or 960 XP. If he thereafter rose to 13th level and picked up
a fourth class (by adding 1st-level cleric, for example), he would take
a –40% XP penalty from then on.
As a second example, consider a dwarf 7th-level fighter/2nd-level
cleric. This character takes no penalty because his fighter class is
favored for dwarves and thus not counted when determining
whether his classes are even. Nor does he take any penalty for
adding 1st-level rogue to the mix, since his cleric and rogue classes
are only one level apart. In this case, cleric counts as the character’s
highest class.
A human’s or half-elf’s highest-level class is always considered his
or her favored class.

I hope that helps. Unless there is errata somewhere i didnt keep up with. then by all means correct me

[Alefiend]

Also, the penalty doesn't apply to prestige classes. Assuming you're human, or playing your race's favored class, you should be able to take that dip with no problem.

[MidgetMarine]

. Assuming you're human, or playing your race's favored class, you should be able to take that dip with no problem.

He's not. I'm actually in his game.
Vanaran Sorceror.

Also, soc, why take spellthief when you could just use spell turning?

[HunterOfJello]

It's worth noting that the vast majority of groups don't actually enforce multiclassing xp penalties. They're a relic from 2nd edition and really don't make sense in 3.5 whatsoever.

[Dusk Eclipse]

First ask your DM if he is using multiclass xp penalties, many groups don't use them because it is a terrible rule and works against it's intended purpose (a character who takes 20 levels in different classes doesn't receive XP penalties; but a class x5/class y 10 does).

[Curmudgeon]

a character who takes 20 levels in different classes doesn't receive penalties
You think having a BAB close to 0 isn't a penalty? All 3/4 BAB and 1/2 BAB classes will contribute +0 to your total with this arrangement.

[Dusk Eclipse]

You think having a BAB close to 0 isn't a penalty? All 3/4 BAB and 1/2 BAB classes will contribute +0 to your total with this arrangement.

I was talking about multiclassing penalties, besides there are enough Full BAB classes that you can expect a reasonable amount of BAB at the end. And if you are using fractional BAB (which I know is a variant and shouldn't be assumed) your BAB will also be slightly better

Edit: Edited my previous post to be clearer.

[nedz]

I don't know Vanaran, where is it from ?

More relevantly: What is the Vanaran Favoured class ?

And yes the rule is stupid, but it is RAW and it appears to be in play in your game.

[Dusk Eclipse]

Vanara are monkey people from OA, can't remember their favoured class though.

[Karnith]

Vanara are monkey people from OA, can't remember their favoured class though.
Their favored class is Shaman, an Oriental Adventures class that, as I recall, is basically a cleric with a limited spell list.

[socball22]

Thank you everybody especially Callin. I've read up on the Spellthief ability more and it doesn't seem worth 20% of all my XP.

[socball22]

It really does suck because my Cha is +7 and if I took one level in monk and took Ascetic Mage then I could get my Cha to AC. Once again though, not worth the 20% XP

[ZamielVanWeber]

Their favored class is Shaman, an Oriental Adventures class that, as I recall, is basically a cleric with a limited spell list.

A cleric with a limited spell list, some nice domain powers, unarmed... stuff, and an animal companion. Being good at.combat makes it funny when they giant size themselves.

[nedz]

There are several ways of getting Cha to AC, if that's all you want.
Have a look here (http://www.giantitp.com/forums/showthread.php?t=125732).

[socball22]

I love you Nedz