I don't remember in detail, but the craft specific buffs/debuffs are extremely important on hard. Kloe's Kaempfer is a MUST (STR -50%, DEF -50%). This makes his S-Craft survivable and you have a nice window where you do more damage thanks to the -50% def. Also try to send Kloe to the other side of the battlefield. Generally i can't stress out enough that you should prefer craft based buffs/debuffs over spell based buffs/debuffs here. The bossfight will be very tight, but after a few retries he should be very doable. Again: Kloe's Kaempfer was my best weapon against him and i also played on hard. Another note: I'm not sure what status ailments he causes, but you need accessoiries against them (i think it was confuse that caused the most trouble for me as i couldn't cover everyone with accesoiries against it).