Fate/Grand Order: Cosmos in the Lostbelt

"After the Incineration of Humanity, an unprecedented quest for the Holy Grail begins..."

As all living beings inevitably compete, history is replete with winners and losers. Our present is determined by history's victors...choices made correctly leading to the proper prosperity in due course. This is called Proper Human History. The incorrect choices and incorrect prosperities are history's losers. Dead-end human histories that were deemed unnecessary and interrupted...discarded even from Parallel World Theory... These are called Lostbelts.