What can I say? I love to grind! Enjoy the destruction that follows!
Cort is not that hard normally. He starts off by casting Mystic Shield, which nullifies normal attacks that aren't arts and halves damage from magic. After 25,000 damage, his shield will break and he will start using "Evil Seru Magic" which is the spell Juggernaut. All of Cort's attacks are dark based so equip Ebony Jewels, and don't worry about defender chains on this fight because he does not use physical attacks.
Chapters:
0:00 start
2:20 fight
7:36 end of fight