The vast majority of video games based on Dragon Ball Z are fighting games, so it came as a surprise when it was announced at Microsoft's E3 2019 press conference that Bandai Namco was working on a DBZ action-RPG. When Dragon Ball Z: Kakarot was first revealed, it was unclear exactly how much of the Dragon Ball Z storyline it would explore, but we have reason to believe that it will run the gamut, starting with the Saiyan Saga and going all the way to the Buu Saga.
It was made clear pretty much right off the bat that Dragon Ball Z: Kakarot would at least go on until the Frieza Saga, and considering how that saga actually ends fairly definitively, it would have made sense for Bandai Namco to stop there. In fact, many assumed that Dragon Ball Z: Kakarot would in fact end after the Frieza Saga, which would leave give players a decent ending as well as leave the door open for sequels or story DLC.
However, Bandai Namco threw a wrench in that theory when it was confirmed that the Cell Saga would be in Dragon Ball Z: Kakarot. The inclusion of the Cell Saga means that Dragon Ball Z: Kakarot will include the bulk of the Dragon Ball Z story, with the only saga left to be confirmed being the Buu Saga. It would be a bit odd for the game to include the vast majority of the Dragon Ball Z storyline and leave out the ending, so the most likely scenario is that the Buu Saga will be included.
Luckily for fans of Majin Buu, there is more evidence that the Buu Saga will be in Dragon Ball Z: Kakarot. In a batch of Dragon Ball Z: Kakarot screenshots that Bandai Namco released as part of Gamescom 2019, it was made clear that Cell is the final boss of the "Cell Saga," not the final boss of the game itself. This seems to be a strong indication that the final boss of Dragon Ball Z: Kakarot will be Majin Buu - or more specifically, his Kid Buu form.
What is the Buu Saga?
For the uninitiated, the Buu Saga is one of Dragon Ball Z's longest storylines. The antagonist it's named after is a magical creature that was created by an evil warlock named Bibidi, who used Majin Buu's incredible power to destroy planets. Majin Buu is eventually locked away, but when he's freed by Bibidi's son Babidi, he proves to be one of the strongest foes that Goku and the Z-Fighters have ever fought against.
Like Cell and other Dragon Ball Z villains, Majin Buu takes on a variety of forms over the course of the Buu Saga. This includes his more powerful Evil Majin Buu form, as well as his most powerful Kid Buu form, which is one of the most dangerous villains in the entirety of Dragon Ball Z. As previously mentioned, it's quite likely that Kid Buu is the final boss in Dragon Ball Z: Kakarot, but that's assuming that the game doesn't include content from the films.
It's also worth pointing out that Dragon Ball Z: Kakarot will have some entirely original storylines and characters as well, which means it could reveal a brand new antagonist to serve as the final boss instead. We've already learned about a sixth member of the Ginyu Force named Bonyu, and even more new characters will likely be revealed for the game. So far it seems like these new characters will be relegated to side quests, but it's possible that some of them could take on a more significant role.
What About Sequels?
If Dragon Ball Z: Kakarot is successful, Bandai Namco will no doubt want to make a sequel to the game. However, if it burns through all of the Dragon Ball Z story material in the first game, some may be confused as to how it will be able to do so. Luckily, there is still plenty of material that Bandai Namco could use if it ever decides to make a followup to Dragon Ball Z: Kakarot.
For example, it could create a prequel series that focuses on Goku's time as a child in the original Dragon Ball anime/manga. Alternatively, it could make an adaptation of Dragon Ball GT, or perhaps the more popular choice, Dragon Ball Super. Before fans need to worry about a Dragon Ball Z: Kakarot sequel, though, the game has to actually come out and be successful, so we'll have to wait until its launch in 2020 to learn more.
Dragon Ball Z: Kakarot launches in early 2020 for PC, PS4, and Xbox One.