What do you mean, the little wriggly ones you throw at fish or the big rock ones that squish people?
"Is it just me, or is this cave moving?"
- Obin the Spelunker’s last words
To experience liberation in the arms of Goran, one must first await the coming of the Uroghi..
The Magma Borer is a large creature native to the extreme world of Crematoria. Scientists and planetologists have yet to be able to explain so many things about the planet and the unknown lifeform that made it possible.
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.