Enter these codes at the title screen to unlock more assist characters.

Code	Effect
L, R, Up, Down, Y, X, Left, Right, A	Gogeta.
Left, Down, Right, Y, B, A	Flying Nimbus.
Left, L, R, Right, Up, X, B, Down	Three-Star Dragon.
Right, A, Up, A, Left, A, Down, A (Repeat 3 times)	Pan.
Right, Down, Left, A, B, Y (Repeat twice)	Yakon.
Right, Left, Down, Up, Right, Left, Down, Up, X, B, Y, A	Goku SS4.
Up, A, Right, B, Down, Y, Back, X	Two-Star Dragon.
Up, Down, Left, Right, Down, Up, Right, Left, A	Golden Frieza.
Up, Left, Down, Right, Up, Left, Down, Right, Up, B	Gogeta SS4.
Up, X, Down, Y, L, R, L, R, Up, X, Down, Y	Great Ape.
Up, X, Up, A , Up, B, Up, Y, L, R	Six Star Dragon.
X , Up, B, Down, Y, Back , A, Right, R, L	Five Star Dragon.
Y, A, B, A, Y, A, B, A	Seven Star Dragon.
Y, Y, X, Right, R, Y, X, A	Yamu.
Y, Y, Y, Y, X, A	Mighty Mask.