Fans of Dragon Ball looking for something to fill the void while waiting for the return of Super might be interested to know that there is a huge epic playing out right now within the Dragon Ball universe -- and it's all made by fans. Dragon Ball Multiverse is a 1000+ page comic created by two French fans, Salagir and Gogeta Jr. Salagir is the main author, and Gogeta Jr. was the main artist before leaving the project in 2012 (the main artist is currently Asura).
The fan-work first started on March 13, 2008, and now spans 50 chapters and 1,300 pages. It has also been translated into 32 different languages. There are assistants that have helped with the production of the comic, who also put out specials taking place in the various universes. The upload schedule consists of three pages per week. There's even a prose version of the manga available to read on the main site written by Salagir.
The comic begins 10 years after the conclusion of the canon manga and takes place in a variety of universes. Similar to how the storyline of Super revolves around different universes going head to head in a tournament, a tournament is held in Universe Zero, a universe where there is no life. This allows the fighters to use their full potential without holding back for fear of casualties. Each universe is different from one another in various ways, including differing timelines and outcomes. The tournament itself is held by the Supreme Kais, and once a winner has been decided and awarded a prize, the links between all of the universes will be cut off forever. The prize for winning is the ability to ask for three wishes from the Namekian Dragon Porunga. In total, there are 20 universes that exist within the story's canon.
All of the universes still follow Toriyama's main storyline, but there are deviations here and there. For example, while the fights are similar, a different character could be the one who defeats a certain enemy. In one universe, Vegeta would be the one who defeats Cell, while Piccolo would be the one in another and so on. There are other examples of changes like this throughout the series and it's interesting to see how much one small change could affect the entire outcome of the series.
Several of the movies are not considered part of the canon storyline in some universes, while canon in others. The Trunks TV special, for example, happened in Universes 12 and 14, but not 16 and 18. Some movie villains also make returns that never happened in the original DB canon. Dragon Ball Super is not canon in any of the universes, due to some of the changes it made to the original Toriyama canon. They also go on to say that GT is not canon because it was anime-only, made too many changes to Toriyama's canon, and "...Vegeta with a mustache, that can't be excused." There is a section on the site's FAQ page about what movies and specials are considered canon and which ones are not. Due to the vastness of the story's universes, they have included a page where you can click on a particular universe to see its canon and how it compares to the canon of another universe.
With all of that said, what are some of the universes like, and who are their most notable characters? Universe 2 is a universe with absolutely no logic. The challengers include various characters from Toriyama's other works like Dr. Slump, and even Toriyama himself takes part in the tournament. Alongside Toriyama and his creations are Mary Sue and Sun Wukong, the original Chinese character from Journey to the West that Goku was based on.
Universe 13 is a universe in which Goku never became a good guy and goes by his Saiyan name. He killed all of the humans and fights alongside Nappa, Raditz, and Vegeta. He goes one to become immortal using the Dragon Balls, and Universe 11's Babidi majinizes him and Bulla from Universe 16. The original main cast belongs to Universe 18. The only difference is it's 10 years after the manga concluded. Universe 11 is pretty much the same, except Vegetto never separated, so he's Bulla's father with Bulma being her mother. Universe Nine lacks the Saiyans, so all of the fighters are all-powerful humans like Videl, Yamcha, Krillin and Tien. In Universe 20, Broly survived the second meeting the Goku and Vegeta, and won the third fight, then went on a rampage killing everyone, so he's the only challenger for that universe.
It seems like a daunting task to look at all of this information and try to understand where to begin, but like with most things, it's probably best to start at the beginning and work your way through this massive epic. Despite how many changes and characters there are, once you start reading, it all becomes clearer and easier to follow. There's a reason this comic has been going on for 12 years. If you enjoyed the tournament from Dragon Ball Super, you will most definitely love this one as well.