Even the most hard core Dragon Ball Z fan might get bored of some of the games that Bandai have released with a lot of them having little to no story and all being fairly similor. That was until Dragon Ball Online came out which put fans in the same world in a massive multiplayer online game.
The newest DBZ game Dragon Ball Xenoverse takes all the best elements from the old fighting games and mixes them up with the story and multi player aspects of Dragon Ball Online.
The story of Dragon Ball Xenoverse follows a time traveling player who takes part in all the most historic fights in Dragon Ball. Where the MMO was set in age 1000 years after Gokus death, DBZ XV is set in age 850. To put that in perspective the Buu saga took place in age 774.
Now with Dragon Ball Battle of Gods the time line shifted. Instead of heading down the DB GT timeline Goku evolved into a Super Saiyan God instead of the SSJ4 version. We still have to wait to see if this game will combine both timelines or stick to the new God Saiyans.