This is my second clear of this game, and my first clear of Hard mode after trying out all of the characters a bit more, and credit feeding through Shura difficulty. Hard is a pretty smooth difficulty increase over Normal. There don't seem to be any significant changes besides the damage enemies do and perhaps the amount of health they have, but it doesn't get too dangerous until the last few stages. If you can beat Normal, you can beat Hard without much more practice. I think it's fairly well balanced as the default difficulty to play on, while Shura can be very punishing if you aren't careful.
After playing all of the characters a bit more, I think I like Kazan as much as Rick, if not more so. He's really fun to play, and he even has a triple jump, so you can do a massive amount of damage to any tanky enemy with a single combo. Kazan is also one of the characters who can do infinite combos, which is especially good on bosses. It's not a guaranteed win as soon as you touch a boss though, since most of them are constantly spawning more enemies that will interrupt you. But when you have an opening, you can burn down their health pretty quick. The infinite is pretty simple with Kazan, just do 4 hits, double tap to dash, and then press attack immediately (without hitting a direction). He does a teleport dash punch that resets his combo back to the beginning, so you can repeat it until you need to stop to get away from another enemy approaching you or something. You can even mix it up a bit by doing a full combo, dashing, then doing another 4 hit combo to juggle the enemy and reset it from there. It's hard to keep that going forever, but only bosses will have enough health for that to matter. Kazan's only weakness is his super attack, which just knocks enemies back and doesn't do that much damage. Other than that, he's super fun to play.
Before doing this run, I also learned a bit more about how to really play this game. Throwing enemies into background objects usually causes them to drop gold or items when they get destroyed, so you really want to make use of that. You'll be able to collect enough gold to buy way more full heal items than you would if you just ignored most of that stuff, like I did in my first clear.
Secondly, and probably just as importantly, if you go into the optional room near the end of stage 9, just before the Metal Frame boss fight (at 1:33:37 (lol)), it prevents the blue lasers from coming on on the left side while you're fighting the boss. This makes it infinitely less annoying to fight him, since you can just lure him to the left side of the screen and stay away from the lasers that are constantly coming at you from the right. You don't even have to fight most of the enemies in that optional room, too. You can just go in, kill one or two, and then leave, and the boss won't be such a pain.
I'm still enjoying this game. Shura seems like it'll be pretty hard, so maybe I'll clear Hard mode with some of the other characters, before I give Shura a shot with one of my favorites (probably Kazan or Rick).
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