Saw this list online of all the different worlds/dimensions Rick and Morty have shown in the first 3 seasons. I think its missing some though (the screaming sun?) plus all the ones they've seen in season 4 so far (shrimp universe, snake universe, etc). Tons of cool possibilities for fun rules.
“Pilot” (Season 1, Episode 1)
• Dimension 35C: The universe with the Mega Trees.
“Lawnmower Dog” (Season 1, Episode 2)
• A universe that looks just like ours, but dogs are in charge.
“M. Night Shyam-aliens!” (Season 1, Episode 4)
• The universe within the Zygirion simulation.
• The universe within the simulation within the simulation.
• The universe within the simulation within the simulation within the simulation.
“Meeseeks and Destroy” (Season 1, Episode 5)
• The reality in which Jerry, Summer, and Beth are zombie-possessed aliens that Morty has to kill.
“Rick Potion No. 9” (Season 1, Episode 6)
• Earth C-137: The universe in which “our” Rick and Morty originated, which they abandoned after they “Cronenberg’d” it. This is the universe the original Jerry, Summer, and Beth currently inhabit.
• An alternate timeline where Rick and Morty die while fixing the Ionic Defibulizer (the universe in which the show currently takes place).
• A “Cronenberg” universe in which everyone was turned into normal humans.
“Rixty Minutes” (Season 1, Episode
• A universe where humans evolved from corn.
• A universe where people eat their own feces (possibly J-19-Zeta-7, where Doofus Rick is from).
• A universe with violent antiques shows.
• Reality C500-A: A timeline in which Beth is a real surgeon who never had Summer, and Jerry is famous.
• A universe in which bears make spiderwebs.
• A universe where all proper nouns begin with Schm-.
• Reverse Height Reality, with the version of Game of Thrones where Tyrion is taller than everyone else.
• A world in which at least one person has ants in his eyes and everything is on fire.
• A universe where it’s “Gazorpazorpfield,” not Garfield, and Lorenzo Music is still alive.
• A universe in which Two Brothers is a movie.
• A world in which SNL’s cast consists entirely of nonsense characters, a piece of toast, and Bobby Moynihan (who is feuding with the piece of toast).
• A world in which Ball Fondlers is a TV show.
• A world in which “Turbulent Juice” is either a movie or a product.
• A world in which cars sneeze.
• A world in which Baby Legs is a popular cop show.
• A dimension where some people have trunks and are discriminated against because of them.
• A dimension where nobody wears pants.
• A world in which there is a whole store for doors, and an abnormally long commercial for it.
• A timeline in which the Smith family is currently playing Chutes and Ladders.
• A timeline in which the Smith family is playing Yahtzee instead of Chutes and Ladders.
• A world where people have hamsters living inside their butts.
“Close Rick-counters of the Rick Kind” (Season 1, Episode 10)
• A dimension in which Rick and Morty are cowboys.
• A dimension where Rick is the “scientist formerly known as Rick,” and he was murdered.
• A dimension where Rick and Morty are green aliens with three eyes.
• The dimension where the Council of Ricks meet.
• The dimension where pizzas eat people.
• The dimension where phones eat chairs, and pizzas are chairs.
• The dimension of weird dodo birds (incidentally, this is the universe that proves Rick and Morty and Gravity Falls cross over, so Gravity Falls, Oregon, could be considered yet another Rick and Morty universe). Also known as the “Doopidoo” dimension.
• The dimension where chairs sit on people, use pizzas as phones, and eat phones as pizzas.
• The dimension where everything is made of butts, farts, toilets, and toilet paper. Also known as “Buttworld.”
• Greasy Grandma World, a dimension that’s filled with grease and “a whole lot” of grandmas.
• J19-Zeta-7, the dimension where Doofus Rick lives. In this dimension, Rick never had kids, so he was forced to use a Morty from…
• A dimension in which everyone looks like Eric Stoltz in Mask.
• A dimension in which Rick, controlled by a genius version of Morty, has a scar and invented the slow-clap (this is the dimension with the Morty human shield).
“Ricksy Business” (Season 1, Episode 11)
• The dimension with the giant testicle monsters and Calaxia crystals.
“A Rickle in Time” (Season 2, Episode 1)
• The Uncertainty Timelines: Dozens of timelines created by slight uncertainties in the wake of time having been frozen for a long period.
• The Fourth Dimension, where the time-traveling testicle is from.
“Mortynight Run” (Season 2, Episode 2)
• The universe inside Roy.
• An interdimensional asteroid that houses Jerryboree.
• The Promethean Nebula (the dimension “Fart” is from).
• A universe where Beth remarries a man named Paul Fleischman, who doesn’t overstep his bounds as Morty’s stepfather.
“Get Schwifty” (Season 2, Episode 5)
• A universe in which giant heads gather planets to compete in an interdimensional music competition.
• Alpha-Betrium, where Ice-T is from.
“The Ricks Must Be Crazy” (Season 2, Episode 6)
• A version of Earth with a Ball Fondlers movie franchise, giant telepathic spider, 11 9/11s, and the best ice cream in the multiverse.
• The Mini-Verse.
• The Micro-Verse.
• The Tiny-Verse.
“Big Trouble in Little Sanchez” (Season 2, Episode 7)
• Nuptia 4, the galaxy’s best couples-counseling institute.
“Interdimensional Cable 2: Tempting Fate” (Season 2, Episode
• The Eyehole Dimension.
• A world where there’s eight Jan-Michael Vincents and 16 quadrants.
“Rickmancing the Stone” (Season 3, Episode 2)
• A post-apocalyptic world where a “boom boom” destroyed modern society.
“Rest and Ricklaxation” (Season 3, Episode 6)
• A world that traps the toxic parts of Rick and Morty’s personalities.
“The Ricklantis Mixup” (Season 3, Episode 7)
• A dimension where Atlantis exists.
• A dimension that’s filled with blenders.
“Morty’s Mind Blowers” (Season 3, Episode
• A universe filled with M.C. Escher–esque staircases where Rick and Morty find a Truth Tortoise.
• Morty’s Menagerie: A world where a giant alien imprisons Rick and Morty in a living zoo.
• An afterlife for dead Floop Floopians.
• Venzenulon 9: A world where the temperature drops below 300 degrees every night.
• A universe where “house hunters” track, shoot, and kill sentient houses.
“The ABCs of Beth” (Season 3, Episode 9)
• The Dimension Without Daylight Saving Time.
• Froopyland, a world that Rick invented for a young Beth.