Beat story mode with Raiya under on the difficulty level.
Beat story mode with Reika under on the difficulty level.
Beat story mode with Chibi under on the difficulty level.
Beat story mode with Marie under on the difficulty level.
Beat story mode with Kiriko under on the difficulty level.
Beat story mode with Lina under on the difficulty level.
Beat story mode with H. Star on the normal difficulty level.
Beat story mode with M. Pow on the normal difficulty level.
Unlock all the previously described hidden characters. Then, beat arcade mode with each of those characters on the hard difficulty level.