A couple of tips, always try to stay at the recommended level or higher for the quest (you can check on the quest description) and you need to keep your equipment updated. So be sure to finish Ramdo's quest in every chapter to buy the new updated gear. For the second boss, I recommend killing the small enemies first, that makes the battle much easier. Keep one character as a healer and you can break their protect spell with Grace's technique. Thanks for the battle feedback I'll revise it in the future, the hands were supposed to die if you killed the main body, that's a glitch thanks for pointing it out.