Okay, when you start the game, beat the soldiers, go in, beat the guards Alfonso sends at you, and keep running in that room's upper floor. Eventually, one of the battles will give you an Electri Box. Now go to the boss. Vyse attacks, and Aika uses Electri Box. Note how much damage that did! Repeat, and you most likely have won by now, if not finish it off!
Hey, me again. To add to my other one, you might want to try and Level up Fina's Purple magic as soon as you get the magic cannon. The final spell is not only powerful, but can be fired for the same amout of SP as the Little Jack's main and standard cannons. In general, purple magic is the best type of magic for Ship Battles.
One of the best ways to get your characters to good levels in any game is to work out their speciality. Try to divide your team into spell casters and warriors (eg Vyse and Drachma for warriors and Aika and Fina for spellcasters). Another good tip is to keep a good variety of magic and spells so that you have the right attack for the occasion. Also, try and get high level blue magic, because it is effective against the soldiers of Valua, and all other yellow types. If you want to find the type of an enemy, look at the colour of their window when you attack them. If you need a particular colour of magic fast, give all your characters that colour weapon. Although these tips might not seem to wise, they're essential to good play!
If you do the bountys and the black spot and train around a bit (note this will take some time) when you fight some simple monsters like I did you will eventually get a moonberry or two. This will help for the monsters and bosses ahead