Ugh. This party is incredibly frustrating and boring at the beginning of the game. Until level ten you can't seriously wail on anything. There's a lot of level-grinding and there's nothing you can do about it. After level 10, however, the Thieves/Ninjas kind of become an afterthought (for me, anyway) as the Black Belts become fists of fury.

It's pretty easy to beat the game with this party, however. At level 25 a Fast spell from a Ninja will make your Masters able to hit Chaos 10-12 times.