Earth 21: The original homeworld of the villains who invaded Earth 18. It could have been a world of great heroes and champions, if not for the madness that consumed the alien J'onn J'onnz into a hatred for the human race when his own people died out. Through his telepathic powers, he perverted the minds and hearts of noble heroes into twisted reflections of themselves. Except for Superman....no, Superman was already evil.....the ship that brought him to earth missing the Kents by only so much and placing him with a much more abusive family in Smallville. He's dead now though, killed by a combined assault of Dr. Doom, Magneto, and the Punisher wielding mystical bullets created by Dr. Strange during the invasion of Earth 18. As for Earth 21.....it is a dead world now as well due to the extinguishing of Sol by the alien entity known as the Sun Eater. This is not to say however that all the villains from this world are dead and gone.
Earth 22: Oooooh yeah.....this here is Wrestleworld....yeah....say it twice brother, where all the earth is protected by Hulk Hogan and his team of Superstars. Whether its the threat of the New World Order, led by Hogan's evil twin Hollywood or the machinations of twisted billionaire Vincent Kennedy McMahon, the Superstars are there. And that's the bottom line.
Earth 23: Earth is enslaved by the conquering hordes of the Aks, a race of beings from Mars. Humanity is either callously murdered for amusement, eaten, or experimented upon for the...ah....gratification of the Aks. Resistance will not be tolerated. As it it says in the Ak creedo 'Ak ak ak. Ak ak ak AK!”
Earth 24: A world created by a 'sonic boom' in the timestream creating ripples throughout it. Here Barry Allen never became the Flash, so there Wally West will never inherit that mantle. Where Superman's ship that carried him to earth flattened Metropolis, but where the young Kryptonian was taken and kept weak and decrepit away from the light of the sun. Where a slight change caused a young Bruce Wayne to be killed rather than his parents, meaning Thomas Wayne is now the Batman and Martha Wayne has slipped into demented laughter. Where Tony Stark has been shot dead by his fiance Kathy Dare. Where Peter Parker never learned the lesson of power and responsibility and has become world famous as Spider-Man but also regularly cheats on his wife Gwen Stacy. Where Victor Von Doom is the Thing and Ben Grimm is the Hulk. Where earth has no Green Lantern. Where Europe has been devastated by the war between Atlantis and Themyscira, and the world may soon follow.
Earth 25: A world where humans are second class citizens and it is the mutants and superhumans who are the masters of the world, led benevolently by Magneto and his regal House of M.
Earth 26: A world where once again, evolution took some odd turns. The super powered champions of this world are Captain Carrot and his Zoo Crew, The Justice Critters, and Peter Porker AKA Spider-Ham. The world where a simple duck name Howard was ripped from and thrust into Earth 0.
Earth 27: Like Earth 25, this is a world where mutants rule the earth.....though that is because on Earth 27....sometimes referred to as Earth X.....everyone is a mutant.
Earth 28: The world of the Kromaggs, a militaristic race that evolved rather than humanity. When discovering inter-dimensional travel the Kromaggs found that they appeared to be unique in the multiverse and were sickened by it. Now they've decided to correct this mistake.
Earth 29: This is no earth here. Not anymore. There is no Milky Way Galaxy either. They have been destroyed after Surtur lit his sword Twilight and began Ragnarok. Surtur grows ever larger, consuming all that is before him like some dreaded star. The only survivors of this destruction are the alien Silver Surfer, who was in the Andromeda Galaxy at the time and the mighty Thor....who to his eternal shame and guilt, fled when Surtur had won. Would that he had stayed and fought, but he's lost all hope that Surtur can be stopped. The alien empires of the Kree, the Skrull, and the Shi'Ar likewise are unsure that Surtur's expansion can be halted. But Surtur is interested in something else......a gigantic snake-like creature....a Spawn of Set...has entered his reality. He's killed it of course, but now the fire demon is interested in perhaps expanding his mass towards other realities as well.
Earth 30: A world where Superman's ship crash landed in Soviet Russia rather than Kansas. A world where the Soviet Union dominates the world and has gone from evil empire to the true form that Communism should be. In theory.
Earth 31: A world where the heroes of earth lost to the serpent god Set. Where seven captured heroines birthed Set's unholy spawn. Six of those Set Spawn departed for other realities, while one has remained on earth, devouring the remnants of life on the planet. There is little left on the surface, but the underworld of Subterrainia and Pellucidar remain. And what of Set himself? Luckily that fiend is locked away within the Eye of Agamotto, endlessly battling the hero Quasar now himself empowered by the Engima Force.
Earth 32: A world called Albion where the British Empire remains in firm control of the planet, after interbreeding with a race of aliens who came to earth centuries ago. Currently, Albion is locked in war with the Kromaggs.
Earth 33: Earth Prime as it is known. It has but one hero.....the mind twisting, meta fictional Ultra Comics. Though there was once another....a boy who had the powers of a god....and now uses these powers in the service of his new god. And this good is not benevolent. No, he sees the infinite earths of the multiverse and wants them ended.
Earth 34: A world where the event known as Inferno was lost, and the world was razed. But thanks to the power of the Phoenix it was reborn into a simpler, agrarian world. A pity, for one of the Set Spawn has made it here.
Earth 35: A world that is truly Something Unique. I'll say no more.
Earth 36: Earth Impossible! A world which was to never have life, much less human life, and yet does. This is thanks in part to the alien known as the Impossible Man who occasionally vacations here and creates and recreates life all his own. At least until that big dillweed Galactus shows up every now and then and destroys it all. What a douche. How's the Impossible Man supposed to impress Mr. Mxyzptlk if he keeps doing that?
Earth 37: A world where things have gone rather badly. A world of Ruins, where what could have once been a glorious world of light is dark and fatalistic. Bruce Banner never became the Hulk, but rather a mass of enormous tumors after the Gamma Bomb went off. Where mutants are schizoid freaks of nature rather than benevolent mutations. Where, off in the distance above Mars, the dead body of Galactus orbits. It is unknown as to what killed (or could kill) this reality's World Devourer....but his body hangs there like cosmic carrion.....and it is being fed upon by a Set Spawn.
Earth 38: A world where the arrival of the Kents to find the infant that would one day become Superman was delayed by a simple nail in the road. As a result, superhumans are not liked or trusted here, though Wonder Woman's Justice League is trying to change that.
Earth 39: A world slightly behind ours....still in the 1940s where the heroes known as the Bat, the Clock, and the Owl amongst others are attempting to eliminate the Nazi menace before it unveils its newest and most impressive weapon: the Overman.
Earth 40: The world of Vandal Savage and other villains who invades earth 20. Destroyed by some monstrous god seeking to eliminate every universe in existence. Also the home of the Squadron Sinister, who barely made it across the Bleed to Earth 0. They seek their comrade on this world. They seek King Hyperion.
Earth 41: A world very much like Earth 0 albeit with some differences. This is the homeworld of the hero called Invincible (though he has disappeared and is unknowingly on Earth 0.....thank Mojo for that) as well as the Noble Family. Very recently the combined heroes of this world fought off another of the Set Spawn.
Earth 42: The Absurdiverse. Home of the Tick and Megaton Man and Lieutenant Frank Drebin. A World where the laws of reality are somewhat...relaxed.
Earth 43: A world where the simple wish of one Cordelia Chase altered things in ways she couldn't imagine. Not that she minds now. She's dead. As are Buffy Summers, Willow Rosenberg, Xander Harris, Angel and others. Where the Master rules Sunnydale and vampires have risen to become a world power due to a snowball effect from that simple wish. Dracula it should be noted is dead. However, somehow the mutant Wolverine has usurped his role and is now Lord of the Vampires. So many of the worlds heroes are either dead or have become vampires themselves (like the Batman). Still there are pockets of resistance. Captain America and Iron Man still fight on the side of the living. The Ghost Rider still rides. The Punisher and Blade have formed a partnership. And there is the Slayer Faith, aided by her friends Daniel Osbourne AKA Werewolf by Night and Tara Maclay, who has become sort of crow empowered revenant.
Earth 44: The uh.....how to put this......Porniverse (or the Per Verse). Here....genetics and morality have taken on wildly different roles. Virtually everyone is of near perfect genetic stock. As a result, people look frankly rather fantastic, have virtually no diseases, and their ….ah....urges...are well....wow. Thus the heroes of this world rarely have anything to do battle with (and in fact there's very little crime due to well....urges). In fact, these constant distractions could very well be detrimental when one of the Set Spawn has entered here.
Earth 45: A world where Spider-Man has joined the Fantastic Four, creating the Fantastic Five. Such a small event. But small events as we've seen can have unforeseen consequences.
Earth 46: A strange Amalgamated world defended by the likes of Dark Claw, Super Soldier, Dr. Strangefate, and a myriad of other heroes.
Earth 47: A world of gods and monsters, where the Justice League still exists, but in wildly different forms. Superman for example is the genetic son of Lara and General Zod. Batman is Kirk Langstrom, cursed with an affliction that makes him a living vampire. And Wonder Woman is Bekka of New Genesis, who came to earth sickened by the hatred that existed between her world and Apokalips.
Earth 48: A feudal world ruled by the Lord Volt and his wife Lady Quark.
Earth 49: A world which is Square, sometimes called Enix. Magic and science exist here in equal portions and for untold centuries the world has called upon champions to defend it, whether that means protecting the Mana Tree or traveling about through time setting things right. And now, a Set Spawn has found it.
Earth 50: The world of the Justice Lords.....wherein these heroes grew dark after the death of one of their own and have since dedicated themselves to protecting the world from itself.
Earth 51: A world where the Confederacy won the American Civil War. As a result, slavery continued and created a whole avalanche of terrible after effects: forced sterilizations to keep slaves from outnumbering owners, the alliance of the Confderate States of America and Nazi Germany, the conquest of and addition of countries to their particular states, with only the Soviet Union and Canada maintaining autonomy. To stem the tide, Queen Hippolyta of Themyscira and King T'Chaka of Wakanda have set up an alliance to keep their own countries safe. This alliance will be sealed by the bond of Hippolyta's daughter Diana and T'Chaka's son T'Challa to be wed. Though not everyone, even in Themyscira and Wakanda, are exactly fond of that idea.