Dragon Ball Z: Kakarot DLC 2 is going to another boss battle episode like the first, but it is still unclear who that boss will be. The first DLC set a precedent by introducing Beerus and Whis, but that doesn't necessarily confirm anything about the DLC to follow. There are a number of possibilities when looking at the vast array of foes that Goku and Vegeta have come up against in Dragon Ball, Dragon Ball Z, and Dragon Ball Super, and though some are more likely than others, theoretically anything is possible until Bandai Namco makes an announcement.
The first DLC saw Goku and Vegeta whisked away to Beerus' planet in order to train with the God of Destruction's attendant, Whis. This training helped players reach the maximum level of 250 and unlock the Super Saiyan God form, both of which would be necessary to defeat the level 250 Beerus boss battle. Now that DLC 1 has run its course, fans can't help but speculate on who the main boss will be in DLC 2. There are of course many theories about who the next boss of Dragon Ball Z: Kakarot will be, as so far Bandai Namco has shared no information about the upcoming DLC.
Golden Frieza in DBZ: Kakarot
The most obvious choice for DLC 2 would be Golden Frieza. Given that Dragon Ball Z: Kakarot has opted to introduce content from Dragon Ball Super with Battle of Gods, the events of Resurrection F would logically follow in the game just as they did in the anime. Golden Frieza would provide a perfect challenge for Goku and Vegeta, and this is also the first time the Saiyans use the Super Saiyan Blue form which is likely to be introduced in the DLC. That said, there are some problems with the inclusion of Golden Frieza.
For one, Frieza is already in the game as a boss for players to fight in the Frieza saga. Though he would certainly have a different moveset as Golden Frieza, it wouldn't bring much to the table to include him again. Additionally, the Golden Frieza saga wasn't actually in the manga version of Dragon Ball Super at all, leading some to believe that Dragon Ball Z: Kakarot may skip Golden Frieza. Finally, unlike Beerus, Golden Frieza never really posed a threat to Goku or Vegeta, as both were much stronger than the tyrant in their Super Saiyan Blue forms, only losing in the anime due to their naivete.
Hit in DBZ: Kakarot
If Golden Frieza is in fact skipped, then Hit will most likely be the main antagonist. Introduced in the Universe 6 Saga, Hit isn't exactly a villain but is clearly the main antagonist of the arc. This character is unique in many ways, as his power isn't derived from raw strength or transformations, instead originating from his martial prowess and unique technique, the Time Skip. If implemented correctly, Dragon Ball Z: Kakarot could make Hit more difficult than Beerus as a boss fight, and the arc does a lot narratively as well.
The theory positing that Hit would be DLC 2's boss arose after a leak suggested that DLC 3 would be the Future Trunks Saga of Dragon Ball Super. The Unlike the Golden Frieza Saga, the Universe 6 Saga introduces fans to the multiverse of Dragon Ball and explains its cosmology in great depth. This kind of detail would be needed in order to contextualize the Future Trunks Saga properly, so it would make a lot of sense to include this. What's more, this is the next saga in Dragon Ball Super which appears in both the manga and the anime.
Broly in DBZ: Kakarot
Very early on fans began speculating about the Legendary Super Saiyan's inclusion in Dragon Ball Z: Kakarot, as a leak showed in game text referring to DBZ Broly. It's now known that this text was in reference to a card for Dragon Ball Z: Kakarot's upcoming card battle mode, but that doesn't discount the possibility that Broly could make an appearance. Given the current trajectory of the game, if Broly does show up, it will almost certainly be the new, rebooted Dragon Ball Super Broly rather than the one from the original Z movies.
The biggest issue of including Broly as DLC 2 is that Goku and Vegeta both have access to Super Saiyan Blue during this fight, so it would imply that Kakarot is not only skipping over Golden Frieza, but the Universe 6 Saga, Future Trunks Saga, and Tournament of Power as well, which seems unlikely. It is more realistic to assume that Broly could end up being a contender for the new story arc coming in Kakarot DLC 3, but this is obviously unconfirmed. Either way, Broly would make a compelling boss fight, as he is not only one of the strongest foes Goku and Vegeta have ever faced, he also introduces Gogeta to the canon of Dragon Ball.
Any Dragon Ball, Dragon Ball Z Movie, Dragon Ball GT, or Dragon Ball Game Villain
Though extremely unlikely, it is always theoretically possible that Bandai Namco and CyberConnect2 will take a completely unexpected route with DLC 2. Villains from Dragon Ball such as Demon King Piccolo could be introduced through use of the time machine, and Dragon Ball Z movie villains like Cooler and Janemba exist outside of canon and could therefore be integrated at any point in Kakarot's canon. There are a lot of fan favorite movie villains that would be great to see, but it is pretty unlikely at this point.
Finally, Dragon Ball: GT has an interesting pre-existing connection with Kakarot thanks to the inclusion of Mira. At the end of Dragon Ball Xenoverse 2, Mira absorbs an egg which contains the entire Dragon Ball GT timeline, so perhaps hunting him down could lead to that. Finally, other video game specific villains such as Android 21 are also found in the world of Dragon Ball Z: Kakarot, but it would be strange to abandon the rest of the Dragon Ball Super storylines in pursuit of those.
Dragon Ball Z: Kakarot is available now for PC, PS4, and Xbox One.