Modified Cleric Class
Note that a PC can only become an Advocate if they begin the game as one unless they are a Monk or Paladin.
These clerics are fairly unique, powerful and generally seldom trifled with by ordinary mortals. (But whoever called adventurerers ordinary?) Advocates serve the will of the Prime God insomuch as they are the Prime God. As a result, they are a cross between your ordinary cleric who casts spells to aid people in her gods name and an angel: appointed messenger of the god to mortals. It is only through Advocates that the Prime God's will is manifest since this belief-forged entity doesn't answer to prayer unlike most gods.
Adventures: Advocates of the Prime God are seldom adventurers in the traditional sense. Most of them wander a set area, helping those in need and rooting out cults and priests of other gods to slay them. Others travel the villages of one or two nations, keeping tracks of births and deaths and marriages for the ruler and acting much as a census taker. Advocates also dispense justice and can be asked by villagers to judge cases instead of local authorities when people wish for an objective view. Generally, only the actual ruler of a kingdom can veto an Advocates ruling but this is rarely done. Advocates who adventure for traditional reasons are generally too young to be law enforcers yet and have too much wander lust to be census takers.
Alignment: Nearly all Advocates favour the Neutral alignmentsm especially Lawful Neutral. Chaotic Neutral Advocates aren't allowed. The others favour the good ones and one can't begin a game as an Evil-aligned Advocate, though some become evil as they grow older. While the Prime God is essentially a composite of all religions, the Advocates don't train evil people to hold the power they have.
Religion: The religion of the Prime God involves Advocates wearing green and red robes lined with silver trim. The robes have no special religious symbol or marking though a non-Advocate wearing one is said to die untimely and the penalty for masquerading as one is very severe. Since the religion of the prime god exists to channel people's belief into a non-religion, there are no religious symbols specifically associated with the belief. Training places for Advocates look like large stone building and, except for the crackling energy around them, could be mistaken for any large stone building sitting in the middle of nowhere.
Background: The background of each Advocate varies and they can be found from every walk of life. Typically, they tend ot be from villages since Advocates visit them often. Almost all Advocates also have some sort of limitation in their natures -- limited magic, physically different* or strange personal habits (such as less socially accepted sexualities or beliefs (feminism)). Advocates will pick people with these limits out in preference to others since an Advocate is supposed to be smart enough not to lord their power over others.
Note that a PC can only become an Advocate if they begin the game as one. Being one is a calling, not something you decide one day to become nor is it one that can be denied. There are 2 exceptions: Monks can become them by channeling their energy out instead of in (class change essentially) as can Paladins. An Advocate can't choose to become one of those classes, as noted in the ex-advocate section.
* As long as the limit can be overcome by being an Advocate (Used a Miracle so you can get around it to an extent (if somone fails a dc 15 Wil check) talk to them telepathically even if you are mute etc.). Being blind, deaf, mute and quadraplegic is a bit much. Alternatively, you could have strong allergies, be missing a limb, ugly or an alibino or whatever else you come up with.Races: Any and all races can become Advocates.
Other Classes: Advocates tend to get feared and respected by others and are often looked upon with suspicion by those who aren't sure what to make of them. Most druids have been harrassed by them a time or two and practically everyone knows someone (or of someone) who was dealt justice by an Advocate that they disagree with or ticked one off and died horribly. Many Advocates try to get around these stereotypes but other -- particularly those of higher levels -- don't give a care any more.
Class Features
Armour and Weapon Pofociency: All Advocates can use simple weapons and most prefer the staff, dagger or club. The more militant ones use maces. They can use all types of armour (light, medium and heavy). The Prime God favours no particular weapon.
Spells: Advocates cast spells as any other cleric does. They can also do spontaneous casting as in the PHB
Domains: Advocates can pick 2 domains they feel best suit their character. Healing, Knowledge and Law are the most common ones.
Lesser Miracle: At will, an Advocate of the Prime God can call down the powers of the god and change the world. This spell can duplicate any spell of level 4 or less at DM approval. Each calling of this power take 1d10% of the Advocates self away, replacing it with the essence of the Prime God and making them less than mortal, and perhaps more. They lose most free will at 10% or less and at 0% become a voice of the god with no personality left in them (an NPC). At level 1, this ability can be used once a day with no harmful effects other than that it can be very addictive. This is the ultimate power of an Advocate and one they use rarely. Each use costs 500+ EXP.
Command People: At level 2 an Advocate can cast a Command spell once a day per level. It is often sued during judgements, such as "Silence!" for annoying people. An Advocate can use all of its effects at once to attfect that many people with the command.
Calm of the Judge Impartial: Can use Calm Emotions once a day begining at level 3.
Discern Lies: This power is gained at level 4 and acts like the spell of the same name. It is usable twice a day, with foes will save modified by your level and wisdom modifier.
Mark of Justice: At level 8, an Advocate can cast the Mark of Justice spell once a day on a person they have rendered a verdict on.
Advocates can not turn or rebuke undead and do not gain any celestial language etc. unless they find a cleric of another religion to teach them it (highly unlikely as that is).
Ex-Advocates
An Advocate is a servant of the Prime God. It is their calling and nature. As such, they can not multi-class at all and only leave their religion to become healers (an option available at level 8, provided they have enough of themself (15%) to make the choice.). Even as healers, they retain clerical spells and any class ability held until that point except the ability to channel the Prime God directly. Once you choose to serve this god, you serve it forever.