The mother crystal made 14 worlds. Our own is the 14th.
If canonically all previous games are those worlds, and nothing else was made after, the ff15 world is from where, and how?
The 13th world was utterly destroyed. It is not the void the voidsent escape from into our world.
Some worlds are taken over by the darkness.
Some worlds are taken over by the light.
Given that at least some of these worlds are past final fantasy games, what ones do you think we messed up badly enough for them to have ended up in darkness?