Here is the basic info on the multiverse: the multiverse in it is finite and has been for a while since an event called the culling of infinity, where a group of human supremacists (from the IRL universe which no longer exists in the setting) destroyed the vast majority of the multiverse, leaving only universes they want left which amounts to 8,541,212. However, their "utopia" fails while they are still making it, as their major restructuring of the multiverse catches the attention of a handful of eldritch gods who all decide to ruin their plans for various reason, a few did it out of spite for humanity, a few did it out of compassion for other species, and a couple did it because it was funny ruining everything they had worked on for millions of years. The end result is that the Supremacists restructured multiverse went wildly different then they expected, with Humanity being the dominant species in less than 1k (the only universes that don't have aliens), humanity making allies with aliens in 6 million universes, and humanity destroying themselves in around 2 million universes. The eldritch gods also did several small changes to their plans that a normal person would think are minor, but leave the supremacists livid (the supremacists are trapped between living and dead only able to observe reality for the rest of time). Also, another thing about the multiverse is that certain events will always happen so long as humanity exists, most were added but the supremacists and modified by the gods but a few were added outright by the gods, some of those events are the moon landing, WW2, rise and fall of the USSR (usually the soviet union turned into a larger communist state which is why it "falls", this is one of the changes made by the eldritch gods, the supremacist added this so that they have someone to look down on in every universe), the creation of communism and fascism, the birth of Joseph Stalin and his rise to power in the Soviet Union (I have yet to meet a fascist IRL that doesn't have a love-hate relationship with Stalin, and I don't honestly know why), to name a few. If this interests you I can tell you more about the main universe we will be focusing on.