I don't think this is reasonable to nohit XD The Supreme Calamitas desperation is a bit hard, and the fact that it takes around 20 minutes to get to that point makes it a little exhausting.
Draedon / Exo Mechs desperation actually isn't that bad, compared to SCAL at least.
Polterghast's desperation is a bit of a mess, I personally think the last attack in that desperation is honestly mainly down to luck, at least in my experience nohitting polterghast before. and again, so many bosses to get to that point. Huge pain.
Devourer of Gods is actually alright, very fun and fair, even in Boss Rush.
There's also night time Providence, if I don't melt her while she's in her defensive phase, she'd shred my health. I nohit Providence before, but I couldn't even normally defeat night-time Providence. Attacks are just way too intense, quick, and absolutely deadly.
For some reason, Astrum Aureus is so quick. Like unbelievably quick. I'm not sure why he walks so fast in Boss Rush.
I'm just really glad Primordial Wyrm / Adult Eidolon Wyrm isn't part of Boss Rush, that'd be messy.
But hey, I'm sure someone skilled enough will come along and nohit this, but so far, out of the few infernum nohitters there are, nobody expressed an interest in nohitting infernum boss rush.
If you wanna do this, use Endogenesis instead of the Cosmic Immaterializer, it deals a ton more damage, I just think it looks distracting and may make the video not be very pleasurable to watch :P
0:00 - Intro
0:09 - Boss Rush
12:14 - Final Tier Boss Rush
21:33 - Loot & Gear