Nice one, okay here goes mine

A - Based on continent that is going through a cival war with the two major leaders fighting to become emperor, but the intial conflict was actually started by a third party that wants to weaken the continents defensive compatibilities for their upcoming invasion.

B- Through an experiment by the sorcery council, they accidentally merged two parallel worlds together with the inhabitants and now sides are being drawn to see who will remain and who will be extinguished ( sort of a modifed version of yours LOST

C- aahhh damn writers block......