I'm not good with these space block things. Again it's only 2 short rooms + 1 long room, and the final long room took me a while, but it never got annoying because I was gradually getting further and getting better at the earlier parts.
Chapter 3 C-side
This one is really annoying. The rhythmic mold enemies are much faster now... and in the 3rd final long room, these things are combined with the angry Oshiro. Even without Oshiro, getting through that section where you go between walls avoiding mold enemies would be really hard, and with Oshiro mixed in, it becomes almost unfair... but after like 200 deaths I eventually learned a consistent play where I can avoid everything and get through it... and then after that there are a few long jumps that require you to bounce off Oshiro's head. That part wasn't that hard, it feels hard at first because it takes so long to get there again if you screw up.
Chapter 4 C-side
This wasn't that bad at all. The final long room was the only room with wind, but the wind kinda helps you more than it hinders you hear. I beat this one in less than 100 deaths.