“ is a lovely golden necklace that gradually transforms its wearer's skin into gold. Given enough time, this will prove fatal, but the wearer cannot remove the deadly jewelry without assistance. Some might be cruel and greedy enough to leave it on its victim...”
“ A city is being plagued by a swarm of winged mice. The vermin can get anywhere, and they can easily avoid their normal predators by simply flying away from them.”
“ 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.”