Yeah by randomness, I mostly meant "hard to predict", in the normal puzzle levels, you generally face the same enemies in the same order, so you can always try stuff until it works, but for he final boss, it can be hard to predict.
And for the controls I did mean I "didn’t know which input direction turns you clockwise and counterclockwise" like I understood the challenge of having to always turn when moving beside shooting, which I think was really cool and interesting, but I never managed to figure out how. I never understood the rule that meant I would rotate clockwise or counterclockwise, clearly there's one, I just... never understood it, so I would often be surprised by the rotation, expecting the opposite.
I think it's mostly because I could get away with trial and error in puzzle levels, but not at the final boss, so something I should've understood by now, I didnt and was very much challenged, so it felt like a steep difficulty curve, not because of the difficulty per say, but because I didnt understand something I should have by then.