Detect Evil Storytime
"At will, a paladin can use detect evil, as the spell."
"...If you are of good alignment, and the strongest evil aura’s power is overwhelming (see chart), and the HD or level of the aura’s source is at least twice your character level, you are stunned for 1 round and the spell ends."
"I don't like using Detect Evil, but it's necessary for my calling. Most people will say so-and-so is evil, but what they really mean is "so-and-so did something that hurt me," or "I feel so-and-so will be dangerous to me at some future date." That's when they're telling the truth; there are some who will try to convince me someone is evil just to get that innocent person out of their way.
"So I have to use the gift given to me by God to detect true evil. I've already said I don't like it, and it isn't easy. It doesn't sort the world into good and evil like sorting beans; it doesn't even sort the world into evil and not-evil. What I get is a sense of just how disgusting and horrible the world can be like.
"How do I describe it? I'll try using smell, though this isn't really smell. Close your eyes, and think back to the last time you had a really good meal, something hot and steaming, something that a loved one made for you. Try to remember what you were thinking: the anticipation of delicious food, how your hunger twinged a little more because you knew it would be sated, how you breathed deep so you could fill your nose and head with more of it's scent. It would seem so natural to tuck into that meal with enthusiasm, wouldn't it? It would be almost inhuman to think otherwise.
"Now, the last time you had to go to the latrine, or a slaughterhouse, or an offal pit, do you remember the smells? Probably not as well as you would remember the meal, and certainly not as cherished. Did you have any sense of hunger, of satiety, pleasure? No, you wanted to just do your business and leave as soon as possible. The concept of spending the whole day there would turn your stomach -- and actually eating while that rank stench pollutes your head? Impossible.
"My God has granted me the sense to "smell" the evil in men's hearts. And it is much worse than any slaughterhouse. Everyone has some smell about them, from venial sins or repressed anger. Even in my own order, we are not flawless, and it is good incentive to live by virtue just so we do not to embarrass ourselves among our peers. But when I have the misfortune of meeting the truly horrible men among us, someone whose very soul is tainted with evil acts committed and evil plans awaiting, my eyes water from the reek of darkness and my meal fights it's way up my throat to escape. It's all I can do not to find it's source and extinguish the malodorous heart by plucking it from its ribs and dashing it on the ground, just so I don't have to put up with it's terrible retching presence."