Original Universe Theory
The Original Universe Theory is considered one of the more creative theories, since it tries to explain how some realities have similar beings. This is also the theory strongly adopted by the multiverse threat that was Alor.
According to this "theory", the Omniverse was initially created as one universe. In this universe, the first sentient beings advanced at an incredibly rapid rate, developing industrialized civilizations, atomic weapons, and space travel all in a matter of generations. Eventually they became powerful enough to be considered gods.
Unfortunately with their omnipotence, these "Original Gods" discovered that their own meddling was causing the universe to come to a premature end. The walls of reality were becoming undone by their manipulations while the universe itself was still young.
To fix this, these gods used their powers to breach the walls of time and space itself, to travel to the impossible moment BEFORE Event One in order to make the chances needed. Once there, though, these "Original Gods" began to quarrel over what needed to be fixed. While they were unified in their conclusion that something needed to be done, they could not agree on how to "fix" the problem.
While they disagreed and bickered, "the event" happened, and the Omniverse came into being again, but this time fractured and fragmented into various multiverse realities based on the views and perspectives of each of the "Original Gods". So while some common elements exist in many of the realities that have since come to be, the various differences that make each reality unique are based on the differences in visions of each of the "Original Gods". Each of the "Original Gods", therefore, became part of their respective realities, which were scattered in all directions during "the event".
While the theory tries to explain both the similarities and differences of the various multiverse realities, the theory falls short in several areas.
The first and biggest criticism is the assumption that one can travel to a point prior to Event One, since it is believed that no such point can exist prior to the first event of reality itself.
Second criticism is the idea that any being could become powerful enough at such an early period of time to where they could endanger all of reality itself. While evolution could occur at varying rates, scientists scoff at the concept that any species could go from sentience to omniscience in a matter of eons instead of millennial-eons