Comics are confusing. There, I said it. Whereas reading a novel series is very linear and easy to follow, comics are a whole different beast entirely. There is not one continuity with various spin-off stories and flashbacks. No, within the main realities of both Marvel's and DC's universes lies something called the "Multiverse." This Multiverse of Marvel and DC is essentially a gateway for all the different realities that exist within the world of superheroes. If you keep up with The Flash, think of Earth 2 as another reality.
It's no secret that the inclusion of these alternate worlds turns away a lot of individuals from ever touching a comic book, but it makes sense story-wise for the writers. By having a multiverse, they can still tell whatever story they want without having major repercussions throughout the main timeline. That's how we got one-off stories and various "What If?" tales over the years. If it's all starting to hurt your head, then don't worry. I love comic books, and I still don't fully understand the Multiverse myself.
Over the years, Marvel and DC have brought their readers across multiple realities and dimensions that were simply breathtaking or different enough to keep things interesting (even the Marvel Cinematic Universe is considered part of the Marvel multiverse). They really went all out for some of the worlds that exist. So get ready to be amazed folks, as we're going to look at some of the best and most astonishing alternate worlds comic books have to offer.
12 Red Son - The Soviet's Superman
Truth, justice, and the American way. That's what Superman stands for. But, what if he landed somewhere completely different? Red Son takes a look at a universe where instead of a humble Kansas farm, Kal-El crash lands in Soviet Russia. He trades in his classic 'S' symbol for a hammer and sickle. He changes his ways entirely, and instead opts to fight for Stalin, socialism, and the international expansion of the Warsaw pact. The U.S. definitely has something to be afraid of.
11 Marvel Zombies
Another horror-inspired universe, but this time in the Marvel multiverse, the Marvel Zombies universe is exactly what it sounds like. A zombie virus broke out, and infected all of the heroes and villains in the Marvel universe. Only a few survivors existed such as Magneto and Black Panther. However, they all ended up being infected. Because of how powerful the Zombies became, they ran out of fresh meat. Galactus showed up to devour the planet, but the Zombies took him down and ate him, in the process being gifted with the power Cosmic. Then they decided to work on a portal to other dimensions in the multiverse to feast on more flesh.
10 Old Man Logan - Wolverine Kills His Friends
Many years ago, Wolverine was mind-controlled into thinking that each of the X-Men were one of his long time villains. Hacking and slashing to kill them all, it was too late once he realized that he had murdered all of his friends. Wolverine then vowed to never use his trademark claws again. Decades later, the world has gone completely sideways. The Red Skull has taken over and most of the Marvel heroes have died. Wolverine, now Old Man Logan, has taken to a quiet life. That is, until the Hulk gang arrives and kills his family. Then with the help of a blind Hawkeye, they go on a quest to set things right once and for all.
9 Battleworld - All-New All-Different Marvel
When Marvel decided to re-launch all of their continuities into the All-New All-Different Marvel, they had to have a way to propel that. That way was Battleworld. Doctor Doom has recreated the world in his image and is now married to Sue Storm. Galactus is now a mere "pet" for Doom's children. Various versions of Reed Richards, Spider Man, Black Panther, Captain Marvel, and Thanos then have to work together to stop Doom from continuing his dark reign over the Multiverse. What ensues is an all out war between Doom's supporters and the various Marvel heroes and villains.
8 Marvel 2099 - The Future
All the beloved stories of Marvel characters we know and love kicking butt and saving the day was referred to as the "Age of Heroes". It all came crashing down eventually, and the world has fallen into a dystopian cyberpunk future. Doctor Doom is now a good guy, Captain America is a villain, and Spider-Man got some impressive new threads. Showcasing a breathtaking new world with some impressive fights was as mesmerizing as it was depressing, as this was the potential future of the main Marvel comics.
7 Justice League: Gods and Monsters
We all know and love the Justice League as symbols of hope across humanity. The moment you hear that sonic boom as Superman flies in to save the day, we all breath a sigh of relief. But what if the Justice League decided to only work for themselves? That's exactly what Gods and Monsters showed us. Instead of staying on the Watchtower waiting for bad guys to take down, the Justice League is now a force of dictatorship that seeks to control the entire world. Superman is now the son of General Zod, Wonder Woman is the widow of the son of Darkseid, and Batman is Kirk Langstrom, known in the main continuity as Man-Bat.
6 Earth 2 - Justice Society of America
Before DC created the Justice League we all know and love today, there was the original Justice Society of America. Touting Alan Scott as Green Lantern, as well as a slew of other vintage heroes, this was part of DC's rise to fame. However, they relaunched their continuities to highlight characters like Batman and Superman for the new Justice League. They then revealed that the Justice Society was still operating, albeit on a different earth. This led to an amazing crossover where the Society and the League both had to work together to stop a terrible threat. Recently Earth 2 made its live-action debut in season 2 of The Flash.
5 Larval Earth - Animal Heroes
Easily the most creative pocket of Marvel's multiverse, Larval Earth is home to a different kind of Avengers. There's Captain Americat, Iron Mouse, the Fantastic Fur, and most notably, Spider-Ham. Yes, everybody in Larval Earth is an animal. This led to some truly hilarious and wonderful moments that only made me want to see more. Larval Earth was first threatened by the planet-eating Galactypus and has since become a beloved part of Marvel's continuity. Larval Earth and Spider-Ham have both made appearances on the Disney XD show, Ultimate Spider-Man. Spider-Ham was also in the SpiderVerse comic.
4 Injustice - Superman Loses Control
What if Superman lost control? That's the question answered by the Injustice comics and video game. The Joker tricks the Man of Steel into killing Lois Lane and her unborn baby, while at the same time, blowing Metropolis into smithereens. Superman then finds the Joker and kills him without hesitation. This started Clark Kent taking over the world in an attempt to bring peace to it. However, he has killed the entire Green Lantern Corps as well as many former members of the Justice League. The only people that are left to oppose him are Batman and his Insurgency.
3 Earth Zero - Bizarro World
A world in the DC multiverse in which every superhero is replaced with Bizarro versions of themselves. Not much else is known about this world, as it only appeared in a few moments of Infinite Crisis. However, it took heavy inspiration from the Bizarro World, which is a planet in the main continuity where Bizarro creatures live. Translating that to a Bizarro Justice League is just too terrifying and weird to ignore. I'm crossing my fingers in hopes that DC chooses to bring it back in future storylines, or perhaps have some characters visit it at some point.
2 Antimatter Universe - Anti-Monitor Threatens The Universe
In the DC multiverse, all of the worlds are named by a number system and composed of living matter. There is one universe, however, that does not adhere to this rule. It is essentially the opposite of the origin of the DC multiverse. And that is where the Anti-Monitor was born, the opposite of the Monitor (a watcher of the entire multiverse). Whereas Darkseid has threatened the Justice League and the world on multiple accounts, the Anti-Monitor has threatened the entire Multiverse, taking more than just a visit from Batman and Superman to be brought down. He even turned the Flash into the God of Death.
1 Ultimate Universe
While Marvel may have a main continuity that everyone thinks of when they see the publisher's name, their second most well-known world is the Ultimate Universe. In this world, Peter Parker was slain and is replaced by Miles Morales, the Fantastic Four are in their early twenties, and, really, so much more has changed. They essentially re-imagined all of their characters for this universe, and it has been a catalyst for many interesting stories. It was actually the Mister Fantastic of the Ultimate Universe who initially discovered the Marvel Zombies.