Gutsco may look intimidating, but in fact he's not difficult to defeat at all. His most annoying attack, Mini, is a gray magic attack that can be easily reversed by using a Mallet or casting Mini on the character inflicted to reverse the annoying affects. Otherwise, he's a melee powerhouse that relies very little on anything else but brute force. That brute force can be your downfall if you don't consciously heal every few rounds - otherwise, direct your own melee attacks and high level spells (anything will do we liked Fira here) and do him in. Medusa, the previous boss to this one, was actually far more difficult. You'll see, if you haven't already.