"Some creatures are best left alone. Cuachac is a giant jellyfish which consumes its prey by stunning it with its poisonous tentacles, then dousing it in a corrosive liquid which slowly reduces the prey into an easy-to-digest pile of gelatinous ooze. Cuachac is best not left alone. Cuachac must be slain." That's probably my favorite FATE description.

As far as actual NPC dialogue, though, I think it would have to be the MNK questline and having the historian's dialogue cut up with <babble>.