A quote from my solo campaign that really got me thinking about how players perceive Npcs.
Does your players treat your precious Npcs like nothing but obstacles, exploits and cannon fodder, whether they are gelatinous cubes or humans?
And if so, what can we do to change it?
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.