Narrator system voices:
Complete All Battle mode to unlock that character’s voice under the “System Voice” option at the “Sound Settings” menu.
EX characters:
Get ten wins in Survival mode in Single Battle. Then, press Left or Right at the character select screen to access a character’s EX form.
Gallery mode images:
Complete Story mode with two characters from the same franchise to unlock the first three rows of images. To unlock the other images, complete Story mode with two EX form characters from the same franchise.