What if some crazy wizard created an artifact that empowered rodents that touched it with one random supernatural power? Preferly right out of the pages of your favorite four-color. (But only one power!) This item does not convey any sort of intelligence boost.
Somewhere along the line, someone very powerful lost their marbles. Literally. Possessing a marble allows incredible clarity of thought about a particular related subject.
Elven prison sentences even for small offenses seem very long to humans, but this is not because their rulers are draconian, but because elves live so long that a six year sentence, for example, is like a six week one in human terms.Humans in Elven countries are well advised to behave themselves