I hate the whole idea of Oaths giving Paladins power. I much prefer the holy warrior who received strength from a deity in earlier editions.
I think the "oath" thing was just put in for people who wanted to play a paladin but didn't want to be religious. I suspect the same thing would happen to the cleric also if WotC could figure out how.
And I agree, being a fallen paladin should mean something. It should hurt, as opposed to being a character build goal.
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I always preferred the anti-paladin from the old Dragon magazine for evil paladins.
