If someone can survive the fourth stage, then the hypothesis is that they will BECOME Lord Blazer, and his existence will become fully real in the physical universe, which will also be the moment that universe ends by collapsing into him—a cosmic event called "the Big Blaze."
The seer with the longest history of high accuracy is Ghost, a person who can only be contacted via the arcane internet and who claims not to exist (hence her identification as a "ghost"). She claims to be able to identify who will become Lord Blazer when the event horizon approaches.
Ghost is also the originator of the goddess-state conundrum hypothesis of neo-goddess theory, in which the number of goddesses existing in a universe determines that universe's eventual fate. 0 goddesses is bad; 1 and only 1 is much worse.
The multi-goddess universe state is the only one she believes provides a long-term chance of universe stability. Failing that, the best outcome is to persist in a 0-goddess state and simply foretell who might become Lord Blazer and kill them.
This is part of why she insists on "interacting with existence despite not existing myself," because of her confidence that the candidate for surviving fourth-stage pyresis will become precognitively clear to her as the Big Blaze comes nearer to the event horizon.