Feion, try giving math skill to a wizard, and put him on auto-battle, save fading life. or auto battle, fight for life i think its called, and target an enemy. Your unit will automatically pick out the best combination and spell, saving you the trouble of checking through all the combinations yourself. The only problem with auto-battle is they usually move into stupid locations, but other than that it's the only time I would ever use auto-battle. Every time that unit gets an AT, you will then see how great math skill is.