Quick and Dirty Soul Eater (3.5e Optimized Character Build)
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Bestowing negative levels before 4th-level spells? Sure, why not? Fighter 5/Soul Eater 1 Warforged
The Book of Vile Darkness is home to a plethora of horrible badness that most characters don't have access to until mid- to high-level. Some prestige classes from there have awkward prerequisites that make them difficult to become. Though hardly the most powerful or broken optimization in the world (some might not even call it an optimization), this shows the quickest possible way to become a favorite from the BoVB: the soul eater.
And what's the key factor? Warforged.
SRD, Book of Vile Darkness, Eberron Campaign Setting, Savage Species
 Game Rule Components
 Spells, Powers, Soulmelds, Stances, etc...
Soul eaters need surprisingly little to become, with most of the basic prerequisites being, well, basic. The tricky part is the race requirement; almost all living non-humanoids with natural attacks have level adjustment and usually racial hit dice to boot. Sure, a minotaur could take his very first class level in soul eater if he really wanted to, but that's not until level 9. And that's no good (pun intended).
Because of how their energy drain ability works, no weapon is necessary; your energy draining slam will be your preferred weapon. Warforged also have innate armor, so unless you took the Unarmored Body feat from Races of Eberron then no armor is necessary either. Wondrous items, rings, and possibly magically enhancing your composite plating is where all your money is going to go. Here are the items my example soul eater is using, using the level 6 NPC wealth of 5600 gp:
- Adamantine Body +1 (1000 gp)
- Necklace of Natural Attacks +1 (1 Attack) (2600 gp)
- Ring of Protection +1 (2000 gp)
Note: If you actually have PC wealth, it might be better to replace the somewhat confusing Necklace of Natural Attacks with an Amulet of Mighty Fists for simplicity's sake.
Starting Ability Scores (Before Racial Adjustments): Elite score array (Str 15, Dex 13, Con 14, Int 10, Wis 12, Cha 8
Race (Templates): Warforged
|Saving Throws||Feats|| Class
|1st||Fighter 1||+1||+2||+0||+0||Adamantine Body, Weapon Focus (Slam)*||Fighter Bonus Feat||Take 2 ranks in Knowledge (Arcana).|
|2nd||Fighter 2||+2||+3||+0||+0||Power Attack||Fighter Bonus Feat||−|
|4th||Fighter 4||+4||+4||+1||+1||Weapon Specialization (Slam)||Fighter Bonus Feat||+1 Strength|
|6th||Fighter 5/Soul Eater 1||+6||+6||+3||+3||Improved Natural Attack (Slam)||Energy Drain 1||Start eating souls here.|
* These feats are key to the build.
The basic idea, as seen above, is to get into the soul eater prestige class as early as possible, letting you bestow negative levels to things at level 6. Most CR 6 enemies have between 7 and 10 hit dice, and a drop of even one can be crippling. Doing it every turn will drop almost all low-level enemies in no time. Death Ward, the ultimate defense against this threat, is a 4th-level spell, so even-level clerics have one level to go before they are safe from you.
Regardless of your other classes, your saves won't be that bad with enough levels in soul eater.
Even with his meager NPC stats and equipment, the example character isn't that bad:
- AC: 21 (+9 Adamantine Body +1, +1 Dexterity, +1 Ring of Protection +1); if you're using some kind of shield, increase to 22 − 25.
- Attack: +11 (+6 BAB, +3 Strength, +1 Weapon Focus, +1 Necklace of Natural Attacks +1)
- Damage: 1d6+6 (20/x2) plus 1 negative level (1d6 slam, +3 Strength, +2 Weapon Specialization, +1 Necklace of Natural Attacks +1)
No "tearing up mountains and throwing them at people" damage, but this is a level 6 barely-half-optimized NPC. Besides, the negative level is the real threat here.
 Munchkin-Size Me
Step one: use something other than the elite score array and NPC wealth. You will instantly see a great increase in power.
Switch out Fighter levels for any terrifying high base attack class, such as Barbarian, Duskblade, Hexblade, or Paladin of Tyranny/Slaughter. This will grant you fewer feats, but since only two are necessary for soul eater, the added class features make up for it.
For some added "oomph" when stealing people's souls, try the feats Beast Strike and Superior Unarmed Strike. Rules for these feats are found in Dragon Magazine 355 and the Book of Nine Swords respectively. Alternatively, take a level or two in monk.
Nowhere in the Energy Drain feature's description does it say that you can only apply one negative level a turn. Maximize your number of attacks with the Two-Weapon Fighting line of feats, the monk's flurry of blows feature, and the warforged feats Second Slam and Jaws of Death to put down even high HD creatures in a handful of full-attack actions. Warforged with a warrior's base attack bonus and a healthy dose of feats can easily have 8 attacks or more per full attack action.
Two races found in Dragon Magazine 317, the Gruwaar and T'Kel, could be used in place of the Warforged. They are fey and monstrous humanoids respectively, both have natural claw attacks, and are level adjustment +0 races. Alternatively, Kobolds with the Dragonwrought feat would also qualify for the class, and can be cheesed to no end. No warforged immunities, but these races have other features that make them just as good for the role.
Throw a few flaws in there for an extra feat or two. You can never go wrong with more feats.
And as always, if you want some extra Strength (and thus melee attack) and you're OK with +1 level adjustment, there's always the Lolth-Touched template. Hell, it even kinda fits with the character concept!
 Side Notes
To use your key ability (Energy Drain), you need to be in the front lines and be able to hit things. Resources need to be spent on keeping your defenses and attack as high as you can make them. The Soul Eater's average hit points can make it dangerous to put up front until you get some of your later class features. Saves may be an issue early on, though this is quickly offset by the class gaining all good saving throws.
Ranged combat doesn't come naturally to the soul eater; the Soul Blast ability gained at 3rd level is powerful but only usable once per day. To battle ranged fighters, you are going to need to burn resources, feats, or take class levels in something with ranged combat ability, such as warlock.
 DM Counters
Undead, constructs, and other creatures with immunity to energy drain. Spellcasters with access to the Death Ward spell also weaken the build. Being incredibly evil puts some spells at odds with your Soul Eater, such as the powerful Holy Word.
As an interesting final note, a warforged soul eater is pretty useless against another warforged soul eater; warforged are immune to energy drain and so cannot steal each other's souls. Nothing stopping them from just battering into a pile of junk, though.