Hit Points: 1d8
Paladins are blessed by the power of their deity that is expressed as an aura of power that radiates around them whenever they stand in opposition to forces that are against their faith. It has a 5 foot radius for every level the Paladin has. Affects the paladin and all of his allies in that area, with followers of the Paladin's own faith getting the most benefit.
The aura does not take effect while sneaking, ambushes (until the Paladin can set himself properly), or any situations other than honorable combat. Well, those are occcasionally fine against direct enemies of the faith. Heretics and blasphemers don't deserve honorable combat after all.
The aura counts as Holy Ground. The primary effects are all weapons and armor are considered magical against angels/demons/arcane beasts. Magic opposed to the faith of the holy aura are harder to cast and spells of the same faith are much easier. Saving throws are rolled with advantage (roll twice take the better result).
Paladins gain Mystic Mutations, one on each even numbered level (2, 4, 6, etc). On gaining the 9th Mystic Mutation a paladin becomes a fully consumed instrument of their god and no longer a Player Character.