“ There are reports of a monster that lurks in the tops of trees and drops down on unsuspecting people. It causes them no damage but it frightens them with a hide-like face with big dead eyes, drooling and barking like a dog while unsuccessfully attempting to have intercourse. The PCs investigate and find that it is the local village moron that is doing the spelunking in the woods. How can they explain this otherwise pleasant and merry man that it is wrong to put on a mask, drop down from trees and attempt intercourse with relatives and neighbours.”
“ Urbants-Creatures that move quickly around on their massive arms, and their 'legs' dangle about from their torso, at about elbow length. They can move fairly quickly, but not as fast as an obese human, and can 'jump' fairly high. Their 'legs' are very powerful, and can kill with one blow. The bad thing is, Urbants cannot block attacks at their heads, which have relatively no neck, from the length of their legs being so short.”
“ While it is within your purview to write long-spanning histories of your world, it is largely unnecessary. If you are running an RPG, do this instead: make a bullet point list of important events that affect the world today, and mysteries that people still don't know. Let these fuel your adventures.”