An Antiverse is practically a universe full of anti-matter instead of your usual normal matter. Physics here might be different or still the same, Beings from this universe will think that the anti-matter they have is normal matter and our universe is anti-matter. It's size is 1.2 septillion light-years. Antiverse applies to all verses below the Voidverse i.e. Antixenoverse, Anti-etc... The largest antiverses are the AntiUNNAMEDverse (aka the unkown antiomniverse).
The antiverses are outside of the UNNAMEDverse but, they contained by the Absoluteverse.
In this universe, colors are inverted. So, this means that humans are colored blue with white hair and scary eyes. Likewise, the Earth has yellow-orange oceans, skies, black clouds, ice, blue deserts, purple grass and forests, etc. The Sun is a cold star colored navy blue. The space is colored white. The stars are seen as black dots as if it were filled with black pepper.