Successfully complete the indicated task to unlock the corresponding difficulty:

Hard: Successfully complete Z Chronicles on the Normal difficulty. 
Very Hard: Successfully complete Z Chronicles on the Normal difficulty. 
Z: Successfully complete Z Chronicles on the Very Hard difficulty. 
Movies 

Successfully complete the indicated task to unlock the corresponding movie:

Credits: Successfully complete Broly's Storyline. 
Movie 1: Successfully complete Frieza Saga. 
Movie 2: Successfully complete Cell Saga.