As requested, behold a (long) list of worlds. Status of each world is listed in parentheses. Colors meant to bring out special worlds. Fun fact: some of these worlds have never been named BEFORE NOW.

WORLD STATUS (As of Arc 4’s Conclusion)
Equis Vitis (Merodi Universalis Founder)
Earth Vitis (Merodi Universalis Founder)
The Hub (Merodi Universalis Neutral Territory: not legally treated as a distinct world)
Equis Double (No Further Contact)
Ardent (Minimal Contact: Openly Hostile)
Equis Lai (Merodi Universalis Founder)
Elemental Four (Merodi Universalis Founder) [The official name for the Elemental Nations]
Binar (Merodi Universalis World)
The Static (Scientific Curiosity)
Neon Chessboard (Empty since the Cube was destroyed)
Earth Tau’ri (Merodi Universalis Founder)
Equis Lovestra (No Further Contact)
Earth Omnic (Minimal Contact: In Turmoil)
The Dark Tower (?????????)
Equis Cosmic (Merodi Universalis Founder)
Esefem (Merodi Universalis World)
Empty Universe One (Scientific Curiosity)
Twilight Realm (No Further Contact)
Equis Concrete (Merodi Universalis World)
Earth Therma (Receiving Aid)
Equis Innocent (No Further Contact)
Equis Simpink (Minimal Contact: Through native Pinkie only)
Merodi Nexus (Scientific Curiosity: Contains one of the green diamond grinders)
Equis Eldritch (Merodi Universalis World)
Equis Ultra Fast (Merodi Universalis World)
Equis Scootertrix (Merodi Universalis World: War Over)
Equis Smooze (No Further Contact)
Equis Nut (No Further Contact)
Duplicator Universe (Sealed in Time)
The Sinkhole (Carefully Handling Relief Efforts)
Gem Vein (Merodi Universalis Founder)
Earth Maw (Undergoing Forced Cultural Adjustment)
University of Doors Campus (Openly Hostile)
Ninth World (Mostly Hostile)
Earth Stand (Merodi Universalis Founder)
Arthur Dent’s World (I have no idea. It’s a good place for sandwiches though.)
Equis Flat (Destroyed)
Over Flat (Also Destroyed)
The Sparkle Census (Allied Multiversal Power)
Azure Relic (Location Unknown)
The Collection (Reformed Multiversal Class 2 Power)
Equis Regarden (Merodi Universalis World)
Equis Fallout (Receiving Aid)
Earth SCP (Blacklisted. And Threatened)
Nautica (Renovated, still Blacklisted)
The Nexus (No Further Contact)
Donut Expanse (…Donuts)
Endless Forest (Scientific Curiosity, Used Regularly)
Earth Alisper (Known and in contact, but not Prospect World)
Equis Melinda (Known and in contact, but not Prospect World)
Earth Sherlock (No Further Contact)
Hell Flagg (Avoided after events of Bloodbath)
Earth C (Unknown location)
Eldritch Embodiment (Don’t try to wrap your head around this. Please, don’t)
Earth-MH1 (USM World)
Earth-ST1 (USM World)
Middle-GW4 (USM World)
Disc-DW2 (USM World)
Earth-AZ1 (USM
E-C137 (Locaiton Unknown)
The Citadel (In Contact with Sparkle Census)
The Various Sweetie Chronicle Worlds (Locations Unknown)
Mushroom World (Merodi Universalis World) (Shhh big secret)
Flipside (Merodi Universalis Prospect World)
Castle Bleck (Destroyed, remnant used in Celestia City)
Earth Ottoman (Merodi Universalis World. They have good food. That's all I know.)
Earth Shimmer (In contact, minimal interaction)
ETSAB Worlds (Includes Earth Shimmer)
The Void (Location Unknown)
[Insert other worlds referenced in Sparkle Census Here. Vast majority: Location Unknown]
Elemental Eight (Merodi Universalis Prospect World)
Heaven Eight (Merodi Universalis World)
Earth-W47 (USM World)
I am not naming all the worlds in Sombra’s Clipshow.
Galaxa Quadrants (‘Earth Starfleet’ Merodi Universalis Prospect World)
The Pinnacle (Location Unknown)
Various Dream Worlds (Scientific Curiosities)
Time Space Administration Bureau (Class-2 Society, friendly)
The Evermore Recursions (Location Unknown)
Undertale Cluster (Blacklisted by choice)
Zhui (Avoid)
Starcros Society (Class-2 Society, hostile)
Outpost Blue-19 (Outpost Universe)
Celestial Machinery (Celestialsapien World)
The Arena (Them's Games)
PPC Outpost (Flower World)
Rosa Ceru (DT Cult World)
Boneball (World of Bones, Scientific Curiosity)

-GM, master of lists.

one forgets how many worlds have come up so far, only remember half so far

Unfortunately, there's more than a few worlds I can't recognize by name alone.

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Arthur Dent’s World (I have no idea. It’s a good place for sandwiches though.)

Earth Sandwich? Earth Forty-Two? Of course, the existence of Earth in that universe is a bit up in the air.

Also, neat to see that it's the USM who's made contact with some iteration of the Discworld. Probably a good thing given how the place reacts to high concentrations of magical energy.

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6542869

If you're curious, just ask about a specific world, I can tell you which one it is/extrapolate on its situation.

-GM, master of curiosity

6542647

Maybe add a hint as to where the world originates from? Eg. "Equis Regarden (origin: Fallout: Equestria)"

Also: Arthur Dent's World should be named Earth Highway (Read the first pages)

6543142
The fact that earth's gone means using "Earth" in the universe's name is dubious.

-GM, master of pies.

6543157
"Earth That Was" then

6543183
It is possible it doesn't have an official name - after all, it was a random dial. They don't name all of them.

-GM, master of dice

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6543186
On that subject, I feel like any universe where aliens are fairly common should probably have a... less specific name I guess?

Like, if they ever make contact with the federation (Star Trek), if they named the universe after Earth, you'd risk alienating (haha) The Klingon Empire, The Romulans, The Cardassians, plus the Dominion and... well the only large empire I recall from the Gamma Quadrant was the Borg and they are... not gonna last if they go there.

Also

Earth-MH1 (USM World)
Earth-ST1 (USM World)
Middle-GW4 (USM World)
Disc-DW2 (USM World)
E-C137 (Locaiton Unknown)
Flipside (Merodi Universalis Prospect World)
Earth Ottoman (Merodi Universalis Prospect World. They have good food. That's all I know.)

Which ones are these again?

6550035

Earth-MH1 (USM World)
Earth-ST1 (USM World)
Middle-GW4 (USM World)
Disc-DW2 (USM World)

All USM worlds that are IMPLIED to exist. Froppy implies a My Hero Academia, Valentine implies a Universe B Jojo's, Gandalf implied a Middle Earth, and Carrot implied a Discworld.

Flipside was a place referenced when they went to Castle Bleck, from Super Paper Mario

Earth Ottoman is a custom world that has never been visited but has been referenced several times as having good food.

-GM, master of pies.

6543005
saturation was in this fic? or mentioned ?what chapter was that and what is their world called again? I forget

6563901
Equis Shimmer, mentioned briefly in 'Reach of the Sparkle Census.'

-GM, master of commentus.

Sombra's Clipshow:

One unidentified world (probably Dragon Ball of some description)
Equis Shimmer (previously mentioned, but actually visited this time. Originally appears in referenced story Oversaturation)
Unnamed world (destroyed by Flagg)
The Nightside (referenced; actually located on an Earth in the Strands. Previously visited in side story Wanderers)
Unnamed Earth Tau'ri alternate (Stargate movie continuity)
Unnamed Earth (Five Nights at Freddy's)
Hall of Forgotten Characters (may be a location on a previously-known world, but is probably a stand-alone universe)
Two unidentified worlds (briefly glimpsed; probably based on memes/VR chat, and Minecraft, respectively)
One unidentified world (referenced obliquely; all we know is that it's probably not based on Legend of Zelda)
One unidentified world (probably part of or near the TSAB)
One unidentified world (Mass Effect)

Plus several worlds that previously featured prominently, and possibly as many as twenty others that remain unidentified (but are most likely known Merodi or USM worlds, for the sake of conservation of detail).

The Various Sweetie Chronicle Worlds (Locations Unknown)

With LSB coming out it might be possible to pick up on a faint trail of Sweetie Chronicler. That would be interesting.

6543142
I consider Arthur Dent's world to be in the Deep Thought Cluster, named after the most prominent/distinctive recurring feature in each universe there, if that helps. Which is probably in or bordering on Gallifreyan space, so be careful about messing with time around there.