“ 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.”
“ An army and navy who work in the same way as others except their rank titles are upside-down. So people start as full generals and those with the rank of private command armies.”
“ A known immortal traveling with the PCs kills an attacker, and is arrested and charged with murder, since immortals cannot kill in self defense, being immortal.”