If we had to pick a favourite Dragon Ball saga, it would probably be the Cell Saga. The storyline has everything: a mysterious stranger with a sword who's capable of obliterating Frieza all over again, a plot that involves cool time travel elements, immense character development for Vegeta, Gohan's ascent as a warrior, and a roster of memorable villains. Oh, and let's not forget about Cell himself — one of the most recognisable bad guys in all of modern fiction.
Anyway, the Cell Saga's looking pretty much perfect in this new Dragon Ball: Sparking! Zero trailer. It obviously confirms all of the playable characters that you'd expect (including Mecha Frieza and King Cold!), and the visuals are looking as impressive as ever.