An Omegavoid is the biggest type of void in the entire Omega Spiral.
It has a special property of being able to completely erase any creature that enters it from all timelines and existence states, whether it is currently existing, not existing, both, or even none at all. Only the strongest omni-gods like Gerald can properly survive in this void.
Also, it is not possible to link an Omega Void to any Collection of Hyperspaces at all. An Omega Void can also repel the millions of Omega Black Holes that it contains and successfully keep them from devouring the Omega Void completely.
That brings up another question: Is the Omega Void sentient? No one knows yet for sure, but an Omega Void has been known to target specific Omega Black Holes that are the most dangerous.