Most of the core classes provide many opportunities for variation. With a wide range of abilities, feats and skills to chose from, the rules provide players with enough choices to round out a unique personality.
Of all the core classes, however, paladins have the least room for uniqueness. They have few skill points, and almost all paladins focus on the same skills: Diplomacy, Heal, Ride and Sense Motive. Feats follow more or less the same pattern — Mounted Combat and its feat tree are practically must-haves because of the paladin’s special mount class ability. While strict codes for combat and behaviour are integral to a paladin’s orderly life, players of paladins sometimes would like a little more variety in the class. The real problem ends up being deities. No matter which deity a paladin worships, her class abilities and spells are always the same. Why should a paladin of Ehlonna be the same as a paladin of Heironeous, or a paladin of Saint Cuthbert the same as one worshipping Yondaila?
The optional rule presented in this article offers paladins a greater variety of powers by making a simple change. In order to select a paladin domain, the paladin gives up her ability to turn undead at 3rd level and selects a domain from the list of paladin domains instead (see below). The domain chosen must belong to the deity worshipped by the paladin. Paladin domains do not provide a list of bonus spells as do cleric domains, but they all feature an associated special ability based on the corresponding cleric domain.
While only Chaos and Evil are banned, paladins rarely select domains other than the ones listed here.
Death: You may use a special death ward effect as a standard action, giving you or a good-aligned creature you touch a bonus on all saves against death effects. This saving throw bonus equals your paladin level -2 and lasts for 1 minute. This granted power may be used a total number of times per day equal to 3 + your Charisma modifier. It is a supernatural ability.
Knowledge: You gain a special divine inspiration power. You may make a special divine inspiration check that functions exactly as a bard’s bardic knowledge class ability, except that it is a supernatural ability. Your divine inspiration bonus is equal to your paladin level + your Charisma modifier, and is usable a number of times per day equal to 1 + your Charisma modifier.
Luck: Once per day as an extraordinary ability, you may reroll one roll you have just made before the DM declares whether the roll results in success or failure. You must take the result of the second roll, even if it’s worse than the first one.
Magic: You may use scrolls, wands and other devices with spell completion or spell trigger activation as a wizard of half your paladin level. Any actual wizard levels you have stack with the effective wizard levels gained from this ability. Knowledge (Arcana) and Spellcraft are class skills for you.
Protection: You can generate a protective ward as a supernatural ability. This protective ward grants you or someone you touch a resistance bonus equal to your paladin level -2 on the recipient’s next saving throw. Activating this power is a standard action. The protective ward is an abjuration effect with a duration of 1 hour. It is usable once per day.
Strength: You can perform a feat of strength as a supernatural ability You gain an enhancement bonus to your Strength score equal to your paladin level -2. Activating this power is a free action. It lasts 1 round, and is usable once per day.
War: You may invoke a special true warrior power as a supernatural ability, allowing you to bypass the damage reduction of any evil-aligned creature. Invoking the true warrior ability is a free action, but it must be activated before rolling your attack. Its effects last for 1 round, and you can invoke it once per day.
Source: Dragon Magazine #328 (Page 90)