Looking for help Optimizing a Spellthief... sort of...

[faeryn]

So I've been actively playing a 3.5e campaign with a group of friends and I've been playing as a Spellthief... well sortof playing a Spellthief anyway...

It started off as a spellthief with a couple levels of Wizard to provide some more beneficial spells but as we advanced we encountered a need for a more permanent divine spellcaster (our clerics keep disappearing) so with my DMs permisison I retrained a few levels of Wizard into Archivist and picked up a couple levels of Mystic Theurge to keep my spellcasting up close to where it was...

Well... now I've found myself in a bit of a bind and am looking for some help to sort out my build so that it will remain functional and versatile at higher levels without sacrificing to much of my spellcasting or melee combat abilities... Our campaign is going into Epic levels and we were told to plan for reaching lvl 40 by the end of it...

So anyway here is what I have currently for my build at Lv15

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Spellthief:2 (DM approved custom Gain: higher BaB and 1st Lv Bonus Feat, loses: ALL Armor proficiencies & armored casting)
Combat Wizard:1 (Fighter Feats Variant)
Archivist:1 3 (Lore ACF)
Abjurant Champion:2
Combat Medic:2
Mystic Theurge:5
Force Missile Mage:1
Rogue:1

...and I have planned to take the following on the way up to 40

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Arcane Trickster:10
Abjurant Champion:5 (3 more levels)
Combat Medic:5 Archivist:6 (3 more levels)
Havoc Mage:5
Force Missile Mage:5 (4 more levels)

so that's 40 levels there... and a result of 20/19 Arcane/Divine caster before any caster level shenanigans...

I've taken the Lore ACF on Archivist as well. I know it doesn't do much good with only 1 class level but that is one of the things I was hoping I could get some help with... I've currently got a Lore check mod of +19 (+11 Int, +5 Headband of Lore, +1 Level, +2 Synergy (r5 Knowledge History)) I'd like to try to bring this up to a +30 or at least as close as possible... Preferably without adding more Archivist class levels or another class...

So before we get into the main issue I suppose I should explain what I'm trying to accomplish with this character... Her background is is a scholar of sorts, she seeks to learn and understand everything, honestly she really is quite a bookworm so Wizard/Archivist both were fairly obvious choices for her class. She's a Half-fire Elemental, which comes into play quite a bit since we are playing in the Eberron campaign setting where elementals are bound and used to power various technologies and she's not all that fond of the treatment of elementals, as a result she's not to fond of most other spellcaster's either... combine a thirst for knowledge with a dislike of the local spellcasters and a spellthief is a rather interesting option...

enough of the backstory though... so anyway...

I took 2 levels of Spelltheif to get steal spell and steal active spell effect, then proceeded to level her other casting classes. 1 level of Rogue to gain that all important 2nd sneak attack die to qualify for Arcane Trickster which will bring her up to 7d6 sneak attack before factoring in enchantments. Despite having 90% of her levels being in spellcasting classes she is primarily a melee combatant. I have the Master Spellthief feat to allow me to progress my steal spell ability with each level of arcane spellcasting i gain, so no need to advance past 2nd level.

Abjurant Champion offers a few class abilities that both enhance her spellcasting and improve her survival in melee combat.

Havoc Mage will grant her battlecast which will be used primarily for casting buffs while attacking. I've seen discussions on various forums about if Battlecast allows for a full-attack or if it is a single-attack only and my DM has ruled full-attack due to it's full round action duration.

Force Missile Mage grants bonuses to my Magic Missile spells, which have wound up being my go-to spells when melee isn't a viable option... plus getting 2 extra missiles is always nice too

Combat Medic non-essential, was selected to grant some improvements to my healing abilities... if it comes down to it I can easily drop this prC and fill in the gap with more Archivist levels or another more beneficial prC

a few other prCs i've looked at and considered:

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Geometer first 3 levels grants an ability much like the Rogue/Spellthief's Trapfinding but applies to magical writing which my DM has a habit of using for his "traps" and getting an ability that would alert me if such a trap were nearby would be quite useful

Magelord was an alternative to the 1 level of rogue for obtaining that 2nd Sneak Attack die... more beneficial as it grants a level of arcane spellcasting as well but the prerequisites were not worth it for a single level dip

Geomancer allowing me to blend arcane and divine spellcasting features sounds like a nice benefit... and I do like many of the other features the class offers but I'm not really able to work it into the build...

Daggerspell Mage I love the structure of this class and if I could I would most certainly be using it in my build, unfortunately the reliance on dual-weilding daggers takes this prC off the list for me. I wield a single Rapier with an empty offhand... I'm actually using the Rogue Blade allowing me to sneak attack constantly due to the Blink effect from the sword.

Bladesinger from Races of Faerun is also a class I considered due to my weapon selection... at 6th level I'd gain the ability to cast any arcane spell with a cast time under 1 standard action as a free action while making a full attack, add my intelligence to my AC, and more... TBH there's not much reason to not take this prC besides the 10 level progression limiting room for other classes and the Races of Faerun variant has it's own spell list rather than increasing existing spellcasting...

So what I'm looking to accomplish here is to maximize my potential in melee combat while still providing high level spellcasting functionality... I'd like to if at all possible change the 20/19 Arcane/Divine to a 20/20 before casterlevel adjustments... then find a way to maximize both casterlevels, particularly the Divine caster since the majority of my buffs are Divine. AC is not currently an issue (in fact my DM may have allowed us to get away with more AC shenanigans than he should have).

Typically I find myself casting Divine Power to bring my BaB up to 15+ and follow up with a repeating Hunter's Eye spell to gain additional Sneak Attack die. For this reason I can't use Bladesinger since both of these buffs are Divine... Since Hunter's Eye is a swift action to cast though I can still perform my normal attack action that turn without battlecast or song of celerity when casting it though. But i'd like to be able to cast Divine Power and proceed with an attack that round as well as have the option to prepare other spells while attacking such as Cloud of Knives or Coat of Arms. It would be great to not lose an attack to cast such spells, and It would allow me to make greater use of my large spellpool. Plus when things get rough I wouldn't have to choose between pulling back to heal and buff the team and continuing to pressure the enemy, I can do both simultaneously... since we keep losing our clerics I find myself having to juggle support and offense quite often.

TBH I'm not opposed at all to dropping Combat Medic for 5 more levels of Archivist... I'd more than likely actually get more benefit from 6th level Archivist than from Archivist:1/Combat Medic:5... but I'd like a second opinion on that first... and perhaps someone might even have a better option than either for me.

Funny enough, despite the fact that adding in Archivist for divine casting was a marriage of necessity I've grown to like the combination and can't really see my character without it anymore...

So.. to recap... the character is first & foremost a spellthief, melee combatant using magic to support herself and her party while unleashing a constant flurry of sneak attacks, stealing spells and spell effects when she can. I'd like to improve her Lore ACF as much as possible with out adding more class levels (though if i do drop Combat Medic then I might gain 5 class levels for this). And I'd like to increase my spellcasting to 20/20 before casterlevel shenanigans and then proceed to inhance my casterlevel as high as possible, specifically on the Divine spellcasting side.

Current feats:
Spellbook Mastery
Dragon Familiar (DM ruled it a requirement in order to obtain a pseudodragon as a familiar)
Item Familiar
Darkstalker
Master Spellthief
Blind Fight
Craven
Combat Casting
Familiar Concentration (house rule: Wizards/Sorcerers gain benefits equivalent to Improved Familiar at Lv1, feat unnecessary)
Weapon Finesse
Practiced Spellcaster (Archivist)

Planned future feats:
Telling Blow
Sacred Strike
Eldritch Erosion
Obscure Lore

so I guess what I need is advice on restructuring my progression... help to get the most out of my sneak attacks... help improving my spell casting abilities and boosting my Divine casterlevel... and help improving my Lore class feature... and suggestions for feats I should pick up (I'm aware of the near essential 1st level caster feats, but sadly learned of them to late, will remember them next time)... Also interested in finding a Rogue ACF to replace Trapfinding (redundant class feature due to Spellthief)

At Lv15 i have a 12/12 CL, 2d6 sneak attack (+2d6 bonus), can steal up to 6th Lv spells (higher than I can even cast), a +19 Lore check, and a character that seems to be a hodgepodge of mismatched prCs... and atleast 25 levels to go in which if I continue with how things are now I'll likely find myself growing progressively weaker than the rest of the party...

Attributes:
Str: 26
Dex: 30
Con: 27
Int: 33
Wis: 24
Cha: 22

OH! One more thing... are there any tricks that can be done with this build to boost my spell save DCs? My character was supposed to focus on Illusion spells originally and I still do have a large assortment of illusions in my spell list that I wish to use more often again but unfortunately keeping my save DCs above our enemies save bonuses has proved nearly impossible... heck I can't even fail my highest level spell's DC with my weakest save on a 1... Earlier levels when save DCs were consistantly higher than save bonuses was fun though... and the reason for taking the feat Familiar Concentration >.< held off a whole horde of enemies with an illusion of a wall while the rest of the party fought another horde attacking from the other direction... those kobolds were so convinced the wall was real they fooled themselves into feeling a wall where there was nothing but air.

I should also mention... my DM has forbid use of the Tome of Battle... I've taken a look through it and have seen quite a few things I'd love to use but sadly cant...

[Unbeliever]

There's a lot going on in the OP.  Too much, to be honest.  You should break it up and add some headings, spoiler blocks, and/or tl;dr in there to help us out.  I think that will help you get more replies. 

Ok, so the goal here is Spellthief (at least a little bit) with hard core spellcasting and hardcore melee abilities.  Given the Spellthief angle, that last part is bound to include sneak attack.  And, TOB is off the table.

How dramatically can you rebuild? Here's my first thought:  you don't need to go the Mystic Theurge route.  If you do end up at level 40, well, it won't matter much.  But, typically, the dual casting thing sounds nice but it usually costs more than it gives you. 

And, you have Archivist, which can give you all the spellcasting utility you need.  So, I'd go a bit divine gish here:  persistent Divine Power, Hunter's Eye, and then whatever melee combat buffs you like.  Archivists have access to Paladin, Druid, Ranger, and Cleric, so their buff capacities are shockingly good.  They also have such broad spell access that you'll never notice the lack of arcane spellcasting. 

Generally speaking, that buffing is where your melee firepower is going to come from.  So, I'd eschew stuff like Abjurant Champion, etc.  You don't need it.  One great approach is Archivist/Anima Mage for easy persistent spells, and then pick a Vestige that gives you some sneaky abilities or whatever.  Mix in Sacred Exorcist for turning, and therefore even more persistent spells, and then laugh maniacally ... I guess.  It doesn't have a ton of hit points, so you'll need to shore those up (Bite of X usually helps a lot), but it's a very potent build.  There are also some good channel spell abilities available that let you attack and cast with nice action economy. 

If extensive rebuilding is off the table, then you're in a bit of a bind.  Your build is very scattered.  I have a hard time parsing it, but isn't your caster level for Archivist appallingly low?  Your post kind of reads like "oh, I want to be great at everything, all class abilities," which is obviously a bit hard (though being a primary spellcaster does help ...).  So, you should consider prioritizing with the concept and what you want to do with it.  As a general rule, taking a prestige class to help out one small aspect that's not really an essential part of the build (e.g., helping out Magic Missile by taking Force Missile Mage) is not worth it. 

[Arz]

Agree on trying to do too much!

Read my guide below for answers to your buffing questions. I don't advise raising DC for spellthief casting, as I personally find the payoff slim for the investments.

Advisements:
1) Replace half-elemental with elemental bloodline.
2) Leadership!

[faeryn]

Unfortunately since it is an ongoing campaign and we are currently 16 levels in (Lv15 due to level adjustment) I can't do a whole lot for restructuring my existing build... My DM will permit me to retrain up to 1/4 my total class levels at any given level. And I've taken advantage of that over the past few levels to retrain quite a few levels of Wizard into other things to get to where I am now... (retrained over the course of 3 levels) When i first added Archivist I had a plan to pick up Erudite as well and level Mystic Theurge, Psychic Theurge, and Cerebremancer to get all 3 up to CL/ML 23 but after the first few levels of Mystic Theurge with Archivist i decided against adding in Psionics... far to much to keep track of...

So I'll try my best to break down what I'm looking for in this post.

Arcane: My focus as an Arcane spellcaster is first and foremost Illusions... Originally my character was meant to be an Illusionist when it came to spellcasting, and for the first several levels she was. But due to growing saves and stifling DCs she's been forced into other spellcasting rolls... a heavy reliance on no-save spells such as Magic Missile & it's variants became a necessity... I'd like to get her Arcane spellcasting back to a point where I can effectively use my Illusion spells again. I even have a few Illusion spells for buffing my melee abilities but they suffer the same issue with Will Saves being abnormally high in comparison to spell DCs.

Divine: My focus as a Divine spellcaster is self & part buffs as well as healing. I try to take a more proactive approach to healing by providing persistent heal X per round and spells such as Healing Spirit that will let me heal an ally while taking another action. Like I mentioned, I prefer options that let me split my focus rather than redirect it.

Melee: By no means do I intend to be the parties heavy hitter... Our Elf Ranger/Scout & Weretiger Ninja both have me beat in that field by a long shot and rightly so... for me my Melee ability is focused primarily in Sneak Attacks. Eventually I plan to pick up a selection of the Ambush feats to gain more bonus effects on my Sneak Attacks, but first I need the class provided SA dice to qualify for the feats. My strength score is low so nearly all my damage in melee comes from Sneak Attacks, and I've gone to great lengths to ensure I can almost always apply Sneak Attack. (Rogue Blade, Greater Truedeath Crystal, Demolition Crystal, Earring of the Darkhidden, Rogues Vest, Mantle of the Predator, Darkstalker, Absurdly high Hide/Move Silent, Changeling)

Lore & Skills: I have the largest skillpoint pool in the party so naturally I'm going to be a bit of skillmonkey compared to the rest of the group... I've put a large number of my skillpoints into Knowledge skills and the basics Spot/Listen/Search/Hide/Move Silent & of course due to being a Changeling Disguise. Since I'm the party's Roguish character i also ended up putting points into Disable Device & Open Lock, and due to spellcasting Spellcraft, UMD, Concentration, & Heal. With Knowledge skills eating up so many points I wanted to boost my Lore ability to effectively replace most of them allowing me to move those skillpoints to skills that need them more.

TBH I didn't actually want to branch my character out so much... it just sort of happened since I was the most versatile member in the party and we were in need of a specific type of character at the time. And being the only spellcaster who shows up to every game also had a hand in that...

If I have to put a Priority to each Area I think I'd have to say it'd be in the following order:

Melee - Sneak Attacks
Arcane - Illusions
Divine - Buffs/Defense
Arcane - Buffs/Defense
Divine - Heals
Arcane - Offense
Skills - Lore
Melee - Everything but SA
Divine - Offense

So with that in mind things that I feel can't be removed from the build would be the following:

Spellthief/Wizard/Archivist/Rogue - obviously the base classes are still needed
Mystic Theurge - removing my 5 levels of Theurge would drasticly cut one or both of my casting classes down...

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I know I don't get anything from Theurge besides spellcasting increase but that 5 level dip is actually what's allowed me to keep my CL close to my class level... I know I would have higher level spells if I focused on one side or the other... but I like the versatility... a CL of 12 at lvl 15 isn't terribly low... though if I can't do anything to improve it then as I level up more it will quickly become a burden...

Arcane Trickster - SA dice and spellcasting increase plus a suite of class abilities to improve my sneak attacks. Why wouldn't I take this prC?

Classes that I'd like to keep but other options may exist:
Abjurant Champion - I don't actually wear an armor so the bonuses granted from this class do help on the defensive side of things, as well as it's offensive bonuses at later levels.
Havoc Mage - Casting spells at the same time as performing an attack is a very useful ability to gain access to.

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Both of these prCs can possibly be replaced with Bladesinger the only downsides to that though are that I wouldn't get to cast Divine spells as a part of my full attack, it would take 6 levels to gain the ability, and I wouldn't gain an increase in spellcasting aside from Arcane Caster Level (Master Spellthief). However I'd add my Int to my AC granting me a higher bonus than Abjurant Champion could ever provide, and If I only took a 6 level dip then that would free up 4 more levels for somthing else.

Force Missile Mage - The benefits of this prC are quite nice... especially at 5th level when you gain a 2nd bonus misisle and the ability to penetrate a Shield spell with any of your Magic Missile spells... I also have a habit of stealing Magic Missile & it's variants from enemy spellcasters.

Stuff I can drop without much trouble:
Combat Medic - Provides to little benefit to actually be worth it... I'd most likely be better off taking 5 more levels of Archivist.


TL;DR
Focus: Heavy Sneak attack, Viable use of Illusions, Divine & Arcane Buffs
on the side: Heals, Arcane Offense, Lore class ability
can be ignored: Melee power (non-sneak attack), Divine Offense

Overall: Plays like a Spellthief or Rogue; utilizes Arcane & Divine magic for Buffs, Support, and Diversion. Has viable offensive magic options when the time calls for it, non-priority. Would like to gain the ability to cast buff & support spells without sacrificing an action to do so.

[Unbeliever]

You're still crazily scattered.  I know what most of the PrCs do, but your way of going about things is not efficient, which is why you end up lagging behind. 

Take the Arcane/Divine thing.  You have this idea of doing both, already a tricky prospect (charopp wisdom is that Mystic Theurge isn't worth it).  But, then you've layered on a bunch of arcane only prestige classes, leaving your divine casting in the basement.  Further, none of these really synergize with the whole illusionist/spellthief concept of the character.

I mean, your Archivist casting is at, what, 8th level?  For a 16th level character that's not going to leave you throwing too many great spells, although Archivist's ability to cherry pick from spell lists so they get mileage out of lower level spells, but still, it's not much divine spellcasting.

Likewise, let's look at some of the PrCs.  You've got Abjurant Champion (but just a couple of levels) and Force Missile Mage (just a dip).  These are fine PrCs, for a character built around them.  Instead, you're talking about taking 5 levels for a spell that's a backup option (not a good idea).  Abjurant Champion fits into a similar category -- if I were building an sneak attacking illusionist, I"d just the obvious resources, Greater Mirror Image, Displacement, Invisibility, etc.

tl;dr:  you want to do everything and maximize lots of little things rather than focusing on the big picture for your character.

One general note.  There's nothing wrong with the more organic (for lack of a better term) you've taken to leveling your character up.  Picking various classes, feats, etc. as they come up can be a lot of fun and it can be very fun character.  You posted asking for optimization help, though, which is what I'm posting. 

An Arcane/Divine/Rogue hybrid (see how much of a mouthful that is) is doable, but tricky to pull off.  The Arcane/Divine combo requires a big commitment to credibly pull off at higher levels, and then you'd rely on the spells from that (Hunter's Eye, etc.) to sell the Rogue element. 

EDIT:  so, that'd look something like Wizard 3/Archivist 3/Mystic Theurge X.  With a dip into Cleric or Sacred Exorcist for Turn Undead so you can nab persistent Hunter's Eye (better with some caster level boosters), Divine Power, and some other buffs like Bit of X or Polymorph, etc.  And, maybe also moving into Havoc Mage or something similar to give you the full attack + spellcasting ability. 

But, that loses the Spellthief and some of the Rogue elements, which shows you how hard this is to make viable.  The other option, if you really are going to go into crazy high levels, is to focus on one aspect and then move to another aspect and so on. 

A lot of this hinges on how optimized the campaign is as a whole.

[faeryn]

Well from what we've encountered so far... I wouldn't exactly call the campaign optimized by any stretch of the imagination... some encounters have been excessively easy, while others... lets just say this is my 3rd character in this campaign...

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Our DM lets us permanency a lot of spells that should never be permanence to begin with... and I've found myself asking him on several spells that I personally don't believe should be allowed as permanent due to the extreme advantages they can provide and so far the only things he's disallowed are spells with a duration under 2 rounds, Divine Power, spells that have an ending parameter (on next hit, after X damage, ect...), & spells of 5th Lv+ (unless a party member is the one to cast Permanency for 5th Lv+ spells). Also can't utilize metamagics in permanence (I tried a few times to justify an extended 1 round spell as a 2 round spell for permanency, DM didn't bye it).

I am open to suggestions... though I will admit I can be a bit stubborn... and as I mentioned before I don't have a lot of leeway when it comes to retraining existing class levels... Any extensive restructuring would have to take place over the course of several levels, and I don't think he'd let me go through another multiple level retraining spree again... so about all I can do is retrain 3 or 4 existing levels at this point... (that's not counting dropping Combat Medic for Archivist again, I just recently did that retrain so I doubt he'd argue with me reverting it)

so as i said in my last post though... my Priority would be to focus on the Spellthief/Rogue element of Sneak Attacks... from there I'd want to move onto improving my Illusions and Buffs... I want to have Illusions as a high priority but on a practical standpoint I'd be better off putting my Buffs higher up in priority... And somewhere along the way I'd love to pick up the ability to cast while attacking in one form or another...

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interestingly enough despite requiring Arcane casting for entry, both Havoc Mage and Arcane Trickster can be used to advance Divine Spellcasting. Neither of them specify that the spellcasting class you advance has to be Arcane like so many other Arcane prCs, they both simply say "in a spellcasting class"

the character gains new spells per day as if he had also gained a level in a spellcasting class he belonged to before adding the prestige class

So that gives me up to 14 levels that can be used to advance my spellcasting as either an Archivist or a Wizard. I looked hard for some Divine prCs that I could easily qualify for... preferably without dipping into Cleric or Paladin... but couldn't find any... So i settled for the next best option, prCs that can advance either Divine or Arcane. And I was lucky enough to find 2 of them that have class features that benefit my build greatly.

And like I said... I'm willing to drop both Abjurant Champion and Force Missile Mage if needed... in all honesty Abjurant Champion was added on suggestion from my DM... my previous build outline had 3 levels of Geometer in it's place and 2 levels left open... and with all the AC shenanigans our DM has let us get away with my AC could suffer the drop from losing Abjurant Champion with little issue... and if I were to end up with Bladesinger in its place I'd actually get a boost to my AC.

OK so here is what I have as a base that either can't or won't change...

Spellthief:2/Wizard:1/Archivist:1-3/Rogue:1

I'll need to either bring Wizard back up to 3 or get an arcane prC with a 1st level entry to bring me up to 2nd level arcane to qualify for Mystic Theurge:5 again...

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I'm aware that the prC isn't worth it but as I said before... that 5 level dip is the reason my spellcasting isn't insanely behind... keep in mind I have 3 levels that provide no spellcasting at all. so either way I end up an 8th level caster on one side or the other... this way I am 8th level on both rather than 8th on 1 and 3rd on the other... it was a calculated decision. If there's a better option that doesn't involve dropping one of the two spellcasting classes I'd love to know about it.

so that is 5 or 7 levels of base classes leaving room for 10 or 8 levels of prCs to get back up to 15th level and 25 levels open for interpretation... but as I mentioned already retraining more than 4 class levels at this time might be pushing it with my DM...

All that I actually have set in stone for those remaining levels, is 10 levels of Arcane Trickster... looking at Magelord again I could see it as a possible addition as well but I believe there are better options than it... especially when compared to entry cost.

if I have to pick one casting class to level over the other, I think I'd have to choose Divine... as you've mentioned it has more versatility in Buffs and having Archivist as my Divine casting class gives me access to all Divine magic spells to cherry pick from. You mentioned taking a dip into Cleric for turn/rebuke... I have to wonder though... is it at all possible to obtain Turn/Rebuke without dipping into Cleric? I'd honestly like to avoid adding another base class dip if at all possible.. it took me till level 15 to finally give in and take a dip into rogue to get that 1 extra SA dice for Arcane trickster...

So lets assume I were to cut off Arcane spellcasting at 9th or 10th level giving me access to 5th level spells and were to from that point focus on Buffs from Divine spellcasting + Sneak Attacks... What do you think we could do with that?

[faeryn]

I have got to stop making such long posts >.<

To try and sum everything up in as short as possible while remaining understandable... TL;DR

I need help restructuring my build from the jumbled mess it is now into a coherent and more practical Spellthief.

I play the character as a melee combatant with spellcasting abilities and have taken a liking to my Divine spellcasting Buffs from Archivist, though the character was originally meant to use Arcane spellcasting Illusions from Wizard. I'd like to, if possible, find a balance between the two while remaining a Spellthief/Rogue melee combatant first and foremost.

I'm currently restricted to only retraining 4 of my existing levels and cannot use anything from Tome of Battle.

My optimization goals are:
Maximize Sneak attack dice
Advance at least one of my Spellcasting classes into Epic spell territory...
Boost CLs as much as possible (Preference on maximizing Divine CL, due to Hunter's Eye)
& Obtain an ability to allow spellcasting while attacking (Battlecast, Dance of Celerity, Spell-channeling, etc...)

a few optional side goals:
Maximize Lore ability
Boost Spell save DCs for Illusions
Obtain more &/or Improve Rogue-like abilities

All-in-all I'm looking for something with more structure than what I have now... and something that will actually improve as I level up as opposed to my current build's path of an obvious decrease in power with every new level from this point forward.



I also just remembered another detail that might help with selecting prCs... DMs house rule removes race restrictions from prCs with a few very select exceptions. The exceptions being any racial prC utilizing specific race physiology (Illithid Savant, for example), and a certain prestige class for Drow (I can't remember the exact class off the top of my head). And any racial prC that uses a racial ability or has such an ability as a prerequisite is usable by any race that has access to that ability, even if the race normally would not have access to the class. House rules that give you more options are great, aren't they?

[Unbeliever]

Every game I've played in waves racial requirements for a lot of things; though I don't know how common it is in the broader community.

Also, you're 15th level, so you've got some cash available.  So, you can use Psychic Reformation and a handful of XP to change up your feats and skills.  Hell, you could also just probably acquire a Wish somewhere and maybe use that, depending on whether your DM is supportive or annoyed about you rebuilding your character for it to better capture the concept.

(Recap below)

I have much more practice building characters from the ground (concept) up, so I might not be the best at this.  Given only 3ish levels to retrain, and the goals described, I'd lose Force Missile Mage, Abjurant Champion, and Combat Medic.  Trading these in for more levels of Mystic Theurge (or any other dual advancing PrC, but I don't know them well off-hand). 

As I mentioned in my initial posts, I'd probably prefer to focus on either Arcane or Divine, but with limited rebuilding options, that's not really feasible.  Also, assuming I'm following the thread right, you're in a little bit of a bind:  you'd like to (and have) play a character with an Illusionist focus, which is pretty arcane-oriented, but the group needs some divine casting, too, and that responsibility (along with trapfinding and a bunch of other stuff) has devolved onto you. 

More Mystic Theurge makes spells your bread and butter, which for anyone dual-casting they really are.  And, you'll be able to get into epic MT before long.  Besides that, I think you need to pickup a way to keep your buffs up constantly -- persistent or house ruled permanency will work -- which then translates your spells into melee firepower and competence.  This is all pretty standard gish stuff, probably the easiest way to do it in this build is to dip into Sacred Exorcist and get Divine Metamagic (persistent spell).  With an Archivist that will give you solid buffs.  And, if you do that don't neglect hardening yourself against dispel magic:  Ring of Counterspells, Enduring Arcana, etc. are essential. 

Finally, all gishy types would love a way to cast and fight simultaneously.  Truth be told, I have found this not to be as super necessary as it seems to be.  It forces you to make decisions, though that's the lot you'll be living with 2 spellbooks bursting with devastating magic as it is.  That being said, the easiest one available to you is Celerity and then getting ways to be immune to or shake off daze.  Just google for it, it's typically a 2 feat and a wand commitment.  Alternatively I think there's a divine spell that also makes you immune to daze.  There are numerous guides to this on the internets.  One nice thing is that essentially casting spells as a swift action will help you get the most out of all the spells you've got available.

Going that route, most of your feats should be changed (see Psychic Reformation).  The ones that seem still relevant are:
Dragon Familiar (I assume the familiar has been around and is part of your character)
Darkstalker (if you're sneaking)
Master Spellthief (keeps the spellthief part of the concept)
Weapon Finesses
Practiced Spellcaster (possibly twice, depending on what caster levels look like)

That leaves you 5+ feats to play around with, which is really quite good.  Craven is always nice.  Item Familiar is unnecessary (you can crank your skill checks up into the straosphere with the right spell), and you've lightened your pre-req load this way.  I happen to like Eldritch Erosion a lot at high levels, but that only matters if the party has a bunch of other spellcasters in it.  I also have a soft spot for Telling Blow if you have a crazy crit range, but you probably have too many demands on your feats to indulge in it.

Finally, you asked about both boosting caster levels and DCs.  There are excellent guides on these around, just google for them.  The one that occurs to me is the Snowcasting route, and the Icemail Armor synergizes pretty well with your build overall. 

Recap

• retrain the classes that are just giving you +1 caster level and not particularly synergistic class abilities like Force Missile Mage, Abjurant Champion, etc.
• as a dual caster, spells are your bread and butter, which puts you in the sneaky gish camp.  So, get persistent spells somehow, one suggestion is dip into Sacred Exorcist for DMM(persist)
• Celerity tricks can get you cast + attack
• Snowcasting tricks can boost your DCs; check caster level guides for more
• Your feats will need to be largely changed (Psychic Reformation if necessary).  They will end up looking something like:  Dragon Familiar, Darkstalker, Master Spellthief, Weapon Finesse, Practiced Spellcaster, Snowcasting, Eschew Materials, Spell Focus (cold), etc.

Hope that helps.

[faeryn]

Feats & my reasons behind the ones I've taken

(click to show/hide)

Spellbook Mastery: My DM houserules prepaired spellcasters as spontanious and gives spontanious spellcasters Spellpoints to keep them at a higher versatility. So adding my Int mod to the number of spells i learn at each level is fairly useful... though with my current abundance of gold not as useful as it was at low levels... I currently have almost 400,000 gold and not much to spend it on...

Dragon Familiar: Indeed the familiar is already part of my character and has been around a while. Our second encounter after bringing in this character was for the express purpose of finding a pseudodragon to befriend and make my familiar.

Item Familiar: My DM doesn't ever award us XP... instead he just tells us when the party levels up... as such in his campaigns if you want to cast spells with an XP component you need a source of "bonus XP"... Item Familiar is one such source... 10% Bonus XP... The same goes for crafting... and that bonus XP doesn't actually count towards your level... some house rules make things a bit more annoying than they should be... So I took Item Familiar, and I'm taking full advantage of it as well... gaining bonuses to skills all around and getting lesser & greater powers for it being an intelligent item... if i'm going to be forced to use a source of bonus XP as an XP pool for spells and crafting then I'm going to use one that gives me more benefits than just XP and take full advantage of it.

Darkstalker: sneaky indeed, combined with a Ring of the Darkhidden, an insane Hide & Move Silent check and I can avoid being seen by most enemies without actually being invisible.

Master Spellthief: Fairly self explanitory, minimize levels in spellthief, but maximize spellthief potential

Blind Fight: I actually don't remember why I took this... I think it was a prerequisite for something else I was going to take but forgot about... and it's benefits are easily replicated with a See Invisible spell

Craven: Most of my damage comes from Sneak Attacks so adding my ECL to my sneak attack damage is rather irresistible

Combat Casting: While I don't actually need the +4 Concentration, if I recall correctly Combat Casting was a prerequisite for quite a few other late game feats and some prestige classes I have taken

Familiar Concentration: After spending an entire encounter maintaining an Illusionary wall and being unable to do much else... having an option to shift concentration of a spell onto my familiar is very handy... though unless i can get my DCs up to a point of being functional spells again this doesn't serve me much use...

Weapon Finesse: Low Str score but high Dex and using a rapier... personally I would have preferred to add my Int instead but to my knowledge the only way to do that is through the Factotum class at the cost of 1 IP per attack... besides I have a Dex mod of 10 and an Int mod of 11 so it all works out.

Practiced Spellcaster: Like any spellcaster who has levels in non-spellcasting... a necessity.

So... your suggestion is to restructure my build to look more like the following?

Spellthief:2/Rogue:1/Wizard:1/Archivist:3/Bladesinger:6/Mystic Theurge:10/Arcane Trickster:10/Epic Mystic Theurge:7

I think that might be do able...  that would give me 7d6 SA, Arcane & Divine Spellcasting of 20+, and Song of Celerity + Bladesong... I'll need to get some feats for Bladesinger though... luckily I already have one of them

Requirements
Base Attack Bonus: +5
Race: Elf or Half-Elf
Skills: Concentration 4 ranks , Perform (dance, sing, any other) 3 ranks , Tumble 3 ranks
Feats: Combat Casting , Dodge , Expertise , Weapon Focus (longsword or rapier)
Spellcasting: Ability to cast 1st-level arcane spells.

It's a shame though that I have to choose between either casting any spell under 2nd lvl Arcane or Divine as a part of my full attack once per day or any level arcane unlimited times per day but gain a 3rd list of spells rather than expand an existing spellcasting class... prCs with multiple versions of themselves make things difficult sometimes...

[Unbeliever]

Ahem Celerity.  A quick google pulls up threads like this one that gives you some sense of how it can be used.  You'll note that there was never a mention of Bladesinger in my posts.  It's not a good PrC:  it has stiff pre-reqs and only partially advances casting.

I've given you an idea of what I'd do given the constraints you've described.  Whether you want to go that route or not is up to you.  I'd suggest looking at the various handbooks on this site; they do an excellent job at sketching the available options for charopp.

[faeryn]

Honestly... besides the feat requirements and ignoring the fact that it has it's own spell progression. Bladesinger:6 looks like a fairly decent prC for my build... in my eyes anyway...

A 6 level dip would grant me my Intelligence as dodge to AC, casting of Arcane spells as a part of my full-attack (not optimal but still usefull), & 2 bonus feats. The Races of Faerun variant may not be as versatile as the Complete Warrior variant but it does give a better payoff for it's requirements. When compared to the Tome and Blood version as well... the one in Races of Faerun comes across as the most complete version of the prC. Also, only Complete Warrior version is half-progression... all others are full progression but have their own tiny spell pool.

The only things about the prC that i feel hurt me are not having access to casting Divine spells through Song of Celerity, and having a 2nd Arcane spell pool.

As for the spell called Celerity... I was honestly unaware of such a spell... I've looked into it now and it is a decent option.. but at the cost of a 4th Lv spell slot and being dazed the following round... I have to say I'd much rather get either the Song of Celerity or Battlecast class feature... TBH I'm not a big fan of spending spellslots to accomplish tasks that could be accomplished with a feat or class feature at a lower cost and more frequently. Especially when the ability lasts only one round and/or has drawbacks. Celerity may accomplish the task for most but to me it feels like an unnecessary expenditure.


I took everything you said in all your posts and made notes and this is what I ended up with.

So my idea at this point is to use Bladesinger to qualify for Mystic Theurge and get access to Song of Celerity... use Mystic Theurge & Epic Mystic Theurge to advance as a Wizard/Archivist, and along the way take 10 levels of Arcane trickster to boost my Sneak Attack and split those 10 levels out to 6:Wizard, 4:Archivist, to close the gap created by Bladesinger. The end result before any other casterlevel modifications are added in would be CL 24/24. Master Spellthief would boost my Arcane CL up to either 32 or 36 (depending on if the 4 Arcane Trickster levels that advanced Archivist would be calculated into it or not). Practiced Spellcaster could then be taken to boost Wizard and Archivist CLs by 4 resulting in CL 36/28 or CL 40/28... at which point I'd still need to find some way to further increase my Divine CL... and a Ring of Arcane Might would further increase my Arcane CL by 1... Archivist:3 will grant me a Lore check of +21 which can be further improved to +25 with Obscure Lore... close enough to my goal of +30 to work for me....

While it may not be perfect, and i'm sure there's plenty of other builds out there that would perform better... your advice lead to this build which seems to fulfill my goals quite effectively. The only area where it's lacking is Divine CL and spell save DCs... with a little feat work I can get the DCs up and if i'm lucky be able to use my illusion spells reliably again.

With this progression my build looks like this at Lv 15: (my BAB has been boosted a bit to reach the +5 req for Bladesinger through customized Spellthief & Rogue classes and approved by the DM)

Spellthief:2/Wizard:1/Archivist:3/Rogue:1/Bladesinger:2/Mystic Theurge:6
Sneak Attack: 2d6 + 5d6 (bonus from equipment)
9th Level Divine spellcasting CL13 (Practiced Spellcaster)
7th & 2nd Level Arcane spellcasting CL16 (Master Spellthief, Practiced Spellcaster, Ring of Arcane Power)
Lore: +21
Hunter's Eye: +4d6 SA

So at this point all I really need is some help raising my Divine CL... I might drop a level of Epic Mystic Theurge to gain a level of Cleric as well, to qualify for DMM for persistent Divine Power & Hunter's Eye...

So... what options does a Chaotic Good Spellthief/Wizard/Archivist have for increasing her Divine CL as high as if not higher than her Arcane CL?

Items? Feats? Spells?

For the most part, (with the spells I currently know and use anyways) this CL increase would be to gain more SA dice from Hunter's Eye, which at my new progression would grant me a +9d6 to my sneak attack... if I were to match my projected CL for Arcane that would bring me up to +13d6...


Question: Would it be possible to use Master Spellthief in combination with multiple instances of Practiced Spellcaster to exceed your character level with your Casterlevel? For example: Spellthief:5/Wizard:5/Arcane Trickster:10
Practiced Spellcaster on Wizard, & Spellthief increasing each CL by 4 then adding them all together with Master Spellthief for an end result of CL28? (CL15+4 Wizard + CL5+4 Spellthief)
or would Practiced Spellcaster apply after Master Spellthief thus in this example giving 0 CL due to CL already being 20 for both classes? (CL15 + CL5 = CL20 +0)
or would it apply before Master Spellthief but not be added together by Master Spellthief resulting in CL24 for both classes? (CL15+4 + CL5 | CL15 + CL5+4)

[faeryn]

OK... after a little revision and approval of a Homebrew prC by my DM I've found myself with a few levels opened up...

Spellthief:2/Wizard1:/Archivist:3/Bladesinger:6/Mystic Theurge:6/Sacred Exorcist:1/Arcane Trickster:10/Mystic Demiurge:7/?:3

(click to show/hide)

Spellthief:2 + Master Spellthief for increased Steal Spell ability & boosted Arcane CL
Wizard & Archivist as primary casting classes, granting access to all available spells.
Bladesinger:6 (Races of Faerun) Int as dodge to AC & Song of Celerity, provides 2nd Lv Arcane spells for entry into Mystic Theurge
Mystic Theurge:6 boosts spellcasting up to 5th Lv spells as Wizard & Archivist (RoF version of Bladesinger has it's own spell progression; DM said I could just treat it as Wizard progression)
Arcane Trickster to gain additional SA dice, progress 4 levels as Archivist and 6 as Wizard bringing me up to 7th Lv Divine & 8th lv Arcane spells(9th Lv Arcane & 2 Lvs shy of Epic if taken after all 6 levels of Bladesinger)
Sacred Exorcist:1 Turn/Rebuke for DMM & another level of spellcasting as Archivist
Mystic Demiurge:7 combines multiple aspects of my Arcane and Divine spellcasting classes and raises various class abilities up a Wizard/Archivist equivilant to my HD (Lore & Wizard Familiar being the most notable); a merger of my Spell Slots from both classes; the ability to use my Int for Bonus spells as Archivist rather than my lower Wis score; and most importantly my higher Arcane CL for casting Divine spells... not to mention 7 Levels will raise both classes into Epic Spell territory bringing my Archivist advancement to 21st and my Wizard advancement to 25th

Arcane CL is boosted by Master Spellthief from 25th to 31st (Spellthief +2; Arcane Trickster +4) an additional +4 from Practiced Spellcaster and +1 from Ring of Arcane Might bringing my final Arcane CL up to 36th. CL36 at ECL37... It's not perfect but it's just about where I would be if I were a single class spellcaster... Also... due to Combined CL I can drop Practiced Spellcaster for Archivist after 5th Lv Mystic Demiurge

I intend to alternate through Demiurge, Bladesinger, & Trickster starting at Lv 17... speeds up getting Combined CL without putting a large delay on Song of Celerity or SA dice should also help to keep my spellcasting evened out as I level.

Alternatively I can take all 7 Demiurge Levels immediately and then proceed from there... this option would delay my decrease in spell power until after I have 8th Lv spells minimizing the impact... though only having up to 8th or 9th Lv spells at Epic levels is still bad...

Basically I think the order will come down to which is more important... Spellcasting or SA dice...

Due to Mystic Demiurge I only need to raise my Divine spellcasting to that of a 21st level character removing the need for a full progression into Theurge... As both casting classes will use the highest CL, in this case my Arcane CL, I need only raise one casting class beyond 21st level...

I'm actually not sure what to do with these 3 levels.. I could take some classes to boost my CL through the roof... I could take some classes to gain some new beneficial abilities... I could take some classes to improve existing abilities... I really don't know what I want to or should do with these levels... at the very least it does mean a 3 level buffer for if we don't make it all the way to 40th Lv as planned..