It's a hard choice between Bloody Palace and Style Combos.
The Bloody Palace is insanely hard at times, you get the worst mixture of enemies, some of the hardest when you really can't afford to fight then, and pulling out of that requires huge amounts of strategy and dedication.
Whereas large combos and style rely on an expert knowledge of the combat system along with split second reactions and the ability to keep yourself out of harms way consistantly, and that becomes very difficult.
I can't really decide, between those two, they're both equal to me, yet scores on missions doesn't show mastery, anyone can get all S ranks on every mission in every difficulty, that doesn't make them the best of the best, and leader in scores on all missions still doesn't mean you're the best in terms of fighting ability.
So for me, it's a very difficult choice, one that I can't really make, I wish I could vote for both Bloody Palace and Combos, as both show true mastery over specific gameplay elements and are pretty much equal.