u/SkyGazer1203

I was thinking it may be that when FA was not lost and was still part of the lands between continent, the Tarnished travelled back in time and killed the Elden Lord. Since the Tarnished caused such an upheaval while not being from that time, time collapsed and cause a time boom(?) in a radius that covered the entire FA. But this is just head cannon with no evidence to support it.