"Some call it 'the Realm of the Builders' - the Ark refers to it as 'Dius Factorsitius Terravae' or 'The Forge of Worlds.' My opinion? Well, I think it's more of a garden, to be honest."
-Author Dreu, van Heinhelm Household Cleric
You receive a vision of a rooftop "somewhere close by", where a rare moss grows; in the vision, you know the moss is suitable for greatly enhancing the effects of certain types of potions. Now go and find that rooftop. Don't fall off. (Of course, rooftop runners *will* be taken for miscreants by the local City Watch....)