Hint: Magic Opposites:
Magic that opposes one another do double damage and magic from the same house does half damage.
Byakko (Chimera) opposes Soryu (Dragon)
Genbu (Butterfly) opposes Suzaku (Phoenix)
Unlock Weapons:
Moonlight Sword: Free all souls in first 28 stages.
Orchid Malevolence: Kill the Hydra in stage 25.