The wizard of many colors, the bird-snake-man in the flesh, let's hear it for
THE RAINBOW SERVANT!
Now a lot of people may be asking yourselves,
Why the heck do I want to be a rainbow servant?
There's one big answer to that.
Cleric Spell Access.
That's right, ladies and germs, at tenth level of this class, you add the entire cleric spell list to your spell known! Bonus - if the cleric spell isn't on the wizard, sorcerer, or bard list, it's cast as a divine spell. This is absolutely incredible for classes with fixed spell lists, such as the warmage.
The domains given throughout the class are also decent (dread necromancers will appreciate being able to cast magic circle). Rebuking air creatures can be all sorts of army of dragons fun. If you enter early, the wings are actually a good, level-appropriate, form of flight as well. And you get to mindread at will.
It's rather less useful for arcane casters that don't automatically know all spells on their lists... like wizards, sorcerers, magewrights, or trapsmiths.
It's all but completely useless for archivists, clerics, and fighters.
But how do I qualify?
Pretty easily. All you need is third level arcane spells, a decent map, and four ranks of knowledge arcana. Oh, and you can't be chaotic or evil. Presumably the giant feathery mind-reading snakes look down upon it.
But how do I qualify... early?
Several ways. As the skill requirement can be filled at first level, all you really need is the third level arcane spell. There are several ways to cheese this.
2nd level entry (that is, "some class 1"/Rainbow Servant1):
-Eldritch Corruption gives you free heightening by two levels. Slap that baby onto a first level spell, and waltz right in. Better be undead, though, or the heavy taint requirement will wind up costing you.
--Since almost all undead get a free feat under taint rules, this is really easy for necropolitans.
-Or be a human and spend four feats on Earth Sense, Heighten Spell, Sanctum Spell, and Earth Spell.
-Or be any race, and spend three feats on Versatile Spellcaster, Heighten Spell, and Sanctum Spell
3rd level entry: An illumian with the Naenhoon Word, heighten spell, and a source of turning/rebuking (probably dread necromancer), can heighten a spell high enough by level 2, and take their first Rainbow Servant level at level 3.
4th level entry:
-Non humans who spent four feats on Earth Sense, Heighten Spell, Sanctum Spell, and Earth Spell.
-A crazy human fighter who took "magical training", "eldritch corruption", Earth sense, Heighten spell, and Earth spell.
-Or a slightly less crazy human fighter who took "Magical Training, Precocious Apprentice, Earth Sense, Heighten Spell, and Earth spell.
5th level entry:
-Be a warmage/dread necromancer/beguiler, and take Heighten Spell and Versatile Spellcaster. A strongly recommended feat combination.
-Or take Earth Sense, Heighten Spell, and Earth Spell.
7th level entry: Wait a second, this isn't early at all! You already qualify for the class normally, you nut.
Wait a second, what's with the casting progression?
Ah, an infamous mistake. The table on the rainbow servant is erroneous. According to the general rules on precedence, the text always is considered correct over and above the table, so the rainbow servant is, in fact, a full caster. Later editions of the book, such as the Portuguese translation, have the table match the text.
In my opinion, the cleric spell access can still be worth it for warmages even with three lost caster levels, provided you can take versatile spellcaster and shift your whole spells/day progression one notch to the right. You'd need practiced spellcaster to keep your CL up, but whatever.
Wow, ten levels of this class really is peachy keen. But where do I go from here?
A few classes stand out.
Seven levels of Mage of the Arcane Order is an excellent choice if you've entered Rainbow Servant early. You end up having every PHB sorcerer/wizard spell spontaneously on tap along with every cleric spell ever published - a degree of versatility matched only by optimized tier ones.
Sand Shaper is an interesting option for a single level dip, but now that you have every cleric spell ever the marginal value of more spells known is far lower.
Now that you can cast divine spells, there are also more prestige class options available to you. Some decent choices include:
*Church Inquisitor(Complete Divine) - the detect evil is redundant, and inquisition domain only gives you a +4 to dispel checks. On the other hand, you do get a d8 hit die, a few nice immunities, and full casting.
*Contemplative (Complete Divine) - Nice class abilities, but, honestly, most people will just take a single level, snag their favorite domain, and move on.
* Geomancer (Complete Divine) - Normally, the second level divine and arcane spell requirement is restrictive, as it only advances one class. You, however, can waltz right in. The obvious breakpoint is level two, where you get your first leylines ability, but if you're gishing the d6 hit dice and 3/4s BAB isn't bad.
* Prestige Paladin (Variant paladin class from Unearthed Arcana) - good for acquiring paladin spell lists and synergizing with CHA. Great with Sword of the Arcane Order. Absolutely awesome with battle blessing.
*Seeker of the misty isle (Complete Divine) - First level grants travel domain, d8 hit dice, 3/4s BAB, good fort and ref. Not much more to say, other than it loses a level of casting progression at fifth and tenth.
*Singer of Concordance (Races of the Dragon) - Assuming you haven't grandfathered your way in by being a dragon, this is still a nice choice. Two levels gives you a bonus domain from a list (including magic domain), and limited immunity to compulsion.
So, what full casting classes are there that automatically know all spells on their list?
-Beguiler
-Blighter (needs alternative source spell)
-Dread Necromancer
-Divine Crusader (needs alternative source spell)
-Healer (needs alternative source spell)
-Warmage
-Witch (DMG example class)
