Problems with a party of only Spellcasters?

Question

Given a party of only spellcasters (and only unique classes, i.e. only one character can take any specific class), what are possible roadblocks or problems the group may run into? Should they be worried about having any frontline fighters? Would the lack of skills become a problem in the long run? What sort of things should the Players be aware of and/or attempt to compensate for?

What sort of things should the DM be aware of and/or compensate for when dealing with a party of pure, unique spellcasters?

Example party (if needed): Wizard (generalist), Duskblade, Spellthief, Dread Necro, Druid

(Edited from two separate questions)

Answer 1

Roles Really Aren’t That Important in 3.5

To begin, spells are the most powerful class feature in the game. Dungeons & Dragons 3.5 doesn’t really care much about roles: you will be more powerful the more magic you have. You will never be more powerful going for a non-magic class, even if the rest of your group is already magical. So I call this party a good idea on that account. Unfortunately, you do have some pretty severe power disparity here...

Tier-1s

Wizard and Druid are two of the most powerful classes in the game. All else equal, they can seriously handle a lot more than a group of, say, Monk, Paladin, Fighter, Rogue, and Healer could, at all but the lowest levels of optimization.

Tier-3-ishes

Duskblade and Dread Necromancer are good classes, certainly capable of holding their own. Both are not-awful without spells (Duskblade being nearly as good as a Fighter would have been, and Dread Necromancer having an army of minions), too.

Tier-4-ish

Spellthief is a pretty weak class, but it’s pretty cool. There’s a Trickster variant from Dragon vol. 353 that’s pretty good (lose all but the first 1d6 of Sneak Attack, a fair few skills, and Trapfinding for Bard-like spell progression and adding the Bard spells to your list), though it may make the character less “theif-y” than the player wants.

If possible, you should make Godsblood Spelltheft available to the Spellthief – select Deities or Domains that are appropriate for your setting. This feat gives the Spellthief some nice reliability: if the spell he steals isn’t so great, he can always use one of his Domain spells. It helps quite a bit.

The Spellthief is also the only character with Use Magic Device on his class skill list, and only the Dread Necromancer also uses Charisma. This makes him pretty ideal for the party’s wand-wielder. In particular, your party lacks access to Cleric spells, which are quite good. Wands require a static DC 20 UMD check, which is possible to hit pretty consistently by mid-low levels. Not all spells are good choices for wands, but judicious use of them can give the Spellthief a lot of options.

You actually do have the four roles...

Despite the fact that you don’t really need them, you do in fact have the four traditional roles. The Duskblade is a warrior-type, the Wizard is your arcanist, Druids can heal quite well with lesser vigor (I recommend he gets a wand of it for keeping everyone topped up between fights), and the Spellthief has Trapfinding and the like. Dread Necromancers provide a pretty good “fifth class” here – minions can be whatever you need them to be, and he’s got decent curses and battlefield control.

Of course... the Druid or the Wizard could very easily handle front-lining (Wild Shape, polymorph, etc.), or trap-killing (summons are great for that), or minions (Animal Companion, Handle Animal, summons), or... just about anything else...

Anti-magic Field

Since this got brought up in a comment, some deals with anti-magic field.

1. It’s a high-level spell.

2. It’s always centered on the caster.

3. It’s got a really small radius.

A caster casts anti-magic field on himself, and he’s done.¹ Even if a warrior gets an Anti-magic Torc, activating it kills all his magic items, and now he’s in a lot of trouble too. And in both cases, they’ve got to get within range of a spellcaster, activate the AMF (or somehow get in range without magic, but a spellcaster who lets that happen doesn’t deserve the name), and then do something before the spellcaster simply leaves. That radius is way too small to easily pin someone in it, and actions are working against you here.

Casters should be aware of AMF, and build for it. Conjuration (Creation) spells that have SR: No fly right through an AMF – the Wizard’s got a lot of those in Spell Compendium in the form of the orb of spells. The Druid’s Animal Companion, and all of the Dread Necromancer’s minions, can operate more-or-less unaffected by an AMF. The Duskblade does have full BAB and good HP and armor, which means he’s about as good as any other warrior in an AMF. The Spellthief is really the only one who will be largely sidelined by an AMF.

Dead Magic Zone

This is like an AMF, without any of the problems of an AMF. Worse, it’s not even associated with an enemy – it just is. Just, don’t use these. They’re pretty bad for a normal game (arbitrary and asymmetric crippling of characters, with absolutely no recourse), and for this party it would just be a jerk thing to do. At that point you might as well just “rocks fall, everyone dies.”

¹ For the purposes of this discussion, I am ignoring the Cheater of Mystra. If you’re seriously playing at that level of optimization, you’re already well out of my league and I cannot help you.

Answer 2

As mentioned in other answers so far, four casters makes a powerful party. I would say that the drawbacks that the players have to think about are:

1. Resource management. A martial character can swing his/her sword all day. Once a spellcaster is out of spells, few options remain to be effective. Devious DMs can bring the party to its knees by sending waves of enemies or several encounters per day (or worse, at night, prohibiting rest). Particularly dangerous could be encounters during watch at night, when perhaps none of the party is rested, resources are drained, and the party is mostly unprepared (see next point).
2. Preparedness. Many obstacles can be overcome as long as the party is ready for them. Spell effects usually are not constant throughout the day, like a fighter's armor would be. Being surprised could certainly make life extremely difficult for a party of casters who have yet to spend actions putting up their defenses.
3. Spell Resistance. This can be a large issue or a minor one for the characters, depending on their spell choices. Wizards who load up on all the flashy area effect damage spells will be rendered far less effective against monsters with decent spell resistance.

As a DM, I think that the best thing to do in order to challenge this type of party is to vary the encounter pace. Throw small encounters at the party, followed quickly by the "real" battle with large enemies, and then even perhaps another wave of skulking enemies. Don't give the characters a break in the action, and throw out some red herrings for them to waste their resources on. Creative characters will learn how to adapt and perhaps appreciate the challenge.

Answer 3

KRyan's answer was great, but covered things mostly from the player angle; this answer is meant to provide some potential concerns from the angle of planning and running the game.

Magic Can Do Anything

No, really. Anything. They even published a time travel spell. Obviously in a real game environment the all-consuming power of the wizard and druid isn't going to be quite as all-consuming, but magic still provides many more options than you might have planned to deal with. In particular, druids and dread necromancers both know every single spell on their list, anywhere, ever, at all times (cleric shares this trait), which means that the spell list for one adventuring day doesn't have to look anything like the one for the previous day.

There's two effective responses to the fact that magic can do anything. The first one is to have a limited book list (many groups have this already because they only own so many books) from which spells may be drawn. The second is to know as much about magic as possible. Either solution, or a combination of the two, can be highly effective.

Since Magic Does Anything Though...

Planning challenging encounters may stretch your creativity quite a bit. In a lot of ways combat encounters aren't necessarily a problem; select opponents that also use spells and/or have interesting combinations of immunities & weaknesses and then play them intelligently. No, the trouble with challenging an all-spellcaster party is that a lot of "traditional" D&D challenges are wholly invalidated by magic. Locked door? Knock and disintegrate want words. Traps? Summons can handle them. Stranded away from supplies? Conjure some. Running out of money? Melt your remaining gold into a gold bar and then start pitching it into fabricate spells. This phenomenon only gets worse and worse as levels accrue - more spell slots become available for low-level "workhorse" spells and higher level spells invalidate more and more encounters all by themselves. Some players create concepts (like "blaster wizard" or "knight-priest of Kossuth") that cause these problems less than others, but since we're talking about potential pitfalls you should keep this in mind and plan some creativity into your encounters. I would personally suggest mental and social encounters that, if they're going to solve them with spells, require creative use of spells.

Power Disparity Means More When Everyone is Magic

As @KRyan already noted, wizards can do everything and druids can do almost everything. Duskblades and dread necromancers have distinct specialties but can help with almost everything - but then spellthieves can only do one or two things. What this means is that if your players want to find unique ways to contribute there's going to have to be some metagame agreement about what niches everyone wants to fill. I, personally, have no trouble with redundant contribution (to wit: druid and duskblade are both frontliners, wizard and spellthief are both stealthy) but if the idea is to exhibit each character's unique abilities you'd best arrange for each character to actually have some of those. This is true across other classes, by the way - that is, if your party was an archivist, an artificer, a binder, a factotum and a warlock we'd still be talking about how the artificer and archivist can do anything, the binder & factotum do most things, and the warlock only really does one thing.

Why does this stand out more when everyone's magic? Because you can see the sharp differences in how much magic is available to each character; they're all drawing on the same kind of resource to varying degrees of capability. This doesn't have to be an issue, but in some groups it is so do keep it in mind.

Optimization Level Matters

This one is in two ways - everyone being on the same op level, and what that op level actually is. It's good advice in general to make sure that your players are playing on the same mechanical level if you can arrange for it at all, but ensuring this for an all-spellcaster group means you can plan encounters for the group as a whole instead of trying to piece them out for individual party members. Additionally, setting an op level (say, mid-op) means you can help out players whose classes are mechanically weaker (like the spellthief) with optimization advice that might help them 'catch up' to more powerful classes - or, alternately, suggest self-nerfs for the more powerful classes.

Overall op level changes the tone of a game. This group in a low-op game, for example, might not cause too many problems - if the wizard is blasting and the druid is just healing and summoning, etc, there's not a whole lot to actually worry about. The higher the optimization level goes, the more work you have to do as a DM - which isn't necessarily bad, but it's something to keep in mind. If your players are better at mechanics than you are, don't be afraid to ask them to tone it back; if you're better at mechanics than your players, either teach them or use a delicate touch. Moreso than the rest of the game, magic resembles rocket tag (and that's saying something considering how much like rocket tag the rest of the game looks in terms of solving encounters), so I'd highly suggest keeping an eye on how encounters go.

Answer 4

Assuming the normal paradigm of 4 encounters per day, give or take one, the party should be fine, as long as they make sure to neither spend all of their resources too quickly nor refrain from spending them at all. If the party is able to dole out their spells cooperatively and intelligently throughout a day, there shouldn't be much of an issue, and since spells can almost always replace skills, that shouldn't be an issue either. Depending on the level and the kinds of monsters being fought, a melee speedbump might be useful, but druids come with Animal Companions, and many spellcasters have summon spells, so that capability could be replaced fairly easily.

The DM should be aware, however, that the party will have very high burst effectiveness, if they decide to unload all of their spells at once, so it might be a good idea to train them not to dump all of their abilities on an (apparent) BBEG as soon as the fight starts.

Answer 5

Well, that's a really weak party at level 1. Once they gain a few levels it'll change. Druids are front line types thanks to Wild Shape & Animal Companion, they just also happen to be great spellcasters (and pretty much anything else you want them to be, including healing capable with the Vigor spells). Wizards are quite possibly the single strongest class in the entire game, and once they get a few levels they can take on anything.

The only thing really capable of stopping them cold are anti-magic fields, which will shut almost everything down (even Wild Shape). But short of that, you're not going to make that group stronger by adding a Fighter. Now a Cleric on the other hand...