Rave Master Cheats

At the title screen press UP, UP, DOWN, DOWN, LEFT, RIGHT, LEFT, RIGHT, B, A. If done correctly you will hear a voice, and Reina is unlocked.

Go to story mode, select Haru and put it on Hard. Beat it without continuing and after round 7, King will transform in a Beast. Beat him and you'll unlock this second form of King, The Beast King.

Beat Story Mode with each character to unlock the Story Edit Mode.

First beat story mode with everyone to unlock VS 2 enemies at once in Free mode. Then select Rear Admiral in Free Mode and set it to 1 on 2 with dificulty set to Hard.
After you beat it, you will have unlocked Outlaw.

To unlock a certain character's round call you have to beat free mode on the 2 vs 1 setting for that character