Fate/Grand Order: Malgenesis

With a sudden divergence of the main timeline, Chaldea is assaulted and wiped out by an unknown force. Ritsuka Fujimaru, blessed by an unlikely miracle, is offered a second chance to save the rest of Chaldea.

Ritsuka must now face the Malgeneses, rogue simulations of Singularities that have uncontrollably mutated and now wage war against each other. The key to saving Chaldea and humanity lies within them...

Age rating because of graphic depictions of violence and other potentially unsettling material. This fanfiction takes place before the collapse of Chaldea at the start of the Lostbelt saga (Epic of Remnants taken into account).

Originally written on AO3, where it will always be updated first. Original story with author notes and formatting can be found here: https://archiveofourown.org/works/22011136/chapters/52527013