I genuinely thought it would turn out at the end that Sburb itself was the enemy. That it was ultimately a destructive force that tricked its victims into creating more versions of itself by creating a Lotus eater fantasy where they become super powerful god-figures by jumping through meaningless hoops and murdering sapient, really rather blameless creatures created entirely to be killed. Rose began to reject the game's terms by not doing the meaningless quests, so it engineered a way to give her powers that "proved" to her that this is the way things have to be.
And "the way it has to be" sucks! Everything on the victim world dies and is replaced by game constructs that are long-lived, technologically adept, enormously strong and colony minded - its quite possible that they're intended to spread throughout the host universe rather than just stay on the one planet. Its a very slow alien invasion. Souls are real, and the game can trap them for eternity, but only those of the chosen few who do exactly what the game wants survive in some form. The fate of "ordinary" people like John's Dad is never investigated - the only thing we can say for sure that survives of them are fragmentary memories of the ghosts of "chosen ones". Presumably the Horrorterrors could have captured John's Dad, indeed, potentially hundreds of timelines of him, but didn't once. Why? Who gains from John being cut off from everyone who isn't, in some way, created by the game?
Given the retcon stuff it actually gets worse - those are inbuilt powers of the game that John ultimately uses to further the agenda of the game itself. Sburb could quite easily retcon itself into a "fresh" unrelated universe and make it so it was always already there.
None of that mattered in the end though, so whatever.