Sounds like one of those things where i just use to reply :"Git gud", but i haven't played the game yet. So i'll do it, then i'll come back and say:"Git gud"
Edit: Yeah, i confirm what i was supposing. Git gud
Considering you said you played through it on Normal mode, 'git gud' is very good advice for you, too.
Also don't even attempt the dream world boss on Hard, I'm warning you in advance.
It just needs some luck.
