Fleet but Frail (3.5e Trait)
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 Fleet but Frail
Seriously, you should thank all of the living gods you can AVOID a hit, because you sure as hell can't TAKE one!
Benefit: You gain a +2 divine bonus to your AC
Drawback: You gain one less Hit Point per level (0 permitted)
Normal: If you're playing under the PF system, this would be a Magic trait.
Roleplaying Ideas: Maybe, in the best of times your character avoids battle altogether, but a more interesting idea is to play this as if you feel that you have been blessed by an uncanny nature which will protect you, no matter how flimsily you are put together! Playing a character with this trait as if you are afraid of any oncoming attack is simplistic, and misses the point of the divine blessing.