The beta will include 11 playable characters: SS Goku,
SS Vegeta, SS Teen Gohan, Cell, Majin Buu, Frieza (Final form), Future Trunks, Piccolo, Krillin, Android 18 and Android 16.
Ranging from
SS - C (with C being the lowest), you can see that Goku and
Vegeta are said to be the easiest to play, whereas Piccolo, Majinn Buu and Frieza present more of a challenge.