1: evidently, our multiverse -just one of an infinite web called the omniverse- is a giant cylinder and our UNIverse is somewhere in the middle, as evidenced by Dr. Charles B. Chungus,

2: our observable universe is the largest dimension in our multiverse, so big, in fact, that it would have to be split into upper (where alien races keep to themselves) and lower (the one that we live in).

3: the other dimensions on Dr. Chungus' scale are...

Heaven, the dominion of The Almighty, a council of various gods and elder gods.

Lalaland, the first one that was NOT created by an elder god, and a virus of sorts that will do whatever it takes to purify the Omniverse, often violently so.

upper thing

lower thing

Hell, the headquarters of an intergalactic empire whose goal is to kill all gods and rule supreme.

The Void, the bottom-most dimension. an inhospitable abyss of deadly black surge where only horrifying parasites, namely towering, armlike infestations can survive.

4: the NES Godzilla Creepypasta is the best story, and any who object get a wallop in the ass with a pool noodle by Bandit Heeler