Yaorochi is quite difficult. I almost want to consider Lumen to be more difficult but Yao has some really deadly patterns. Cutting Dance is like top 2 hardest attacks in the game. Habakiri Sword (spell 3) is also really annoying and sometimes just throws really ridiculous shit at you. Non 1 is pretty infamous as if you pick the wrong gaps you can just get walled. Non 3 is an actual attack if you aren't play Tsuba and it's quite challenging too. Everything else is pretty easy.
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