So my 1st playthrough is nightmare difficulty, I didn't actually find it difficult, since I'm just using sp regen ↑ and ↑↑ and spamming skills all the time on all bosses. The only hard parts are oceanus the oversized lovecraftian abomination( you can't spam skills on the bastard), dana's bosses where I really have to block and dodge(I literally have no potions cuz I didn't know you get boss fights, I thought it was all on the PS4 ver.), and the time I forgot to equip the undead-be-gone bell on reaper basileus. I was like dead killing his minions while he kills me with meteors, I spent 30 mins before I died and then remembered the fucking bell, I killed him in 2-3 mins after that. I was like WTF lols.