“ 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....)”
“ The Californian Sea Otter, as a species, eats about 30 different types of food found throughout its range. Each individual otter, however, will only eat 3 or 4 of these foods - those it was fed by its mother as a child. It will not eat the others even if failure to do so means it would starve. Maybe other, possibly larger and more dangerous creatures and monsters, have similar habits.”
“ When you sleep, your soul briefly returns to the place where it was created/goes to when it dies, and seeks nourishment. Everybody's soul is created with a little link (or you could say a greater entity calls it back) to that place so that it can return easily, but upon death, the soul returns via that and annihilates the link as if returns.
Also, as an added thingy, you could say the entity supplying the link, or residue of the links themselves, (whichever) is the source of all arcane power.”