How to beat Reala:
Use normal attacks only.
Heal NiGHTS when his HP (Hit Points) is under 600.
Heal Shadow when his HP is under 300.
Don't waste Shadow's SP (Skill Points) with 'Special' attacks.
Don't waste Shadow's MP (Magic Points) on 'Energy Beam'.
Don't waste NiGHTS' MP on 'Star Rain'.
First time you get enough OD (OverDrive) use SP Outbreak.