How do you cheat in this game? The hp value in cheat engine never sticks? The muffet fight is an absolute joke of a fight in terms of difficulty. Doesn't help you can't use the arrow keys to control the heart...
It's pretty difficult to get the HP value to stay. All you really need to do is change the value type from "4 bytes" to "all" and leave the scan type at "exact value" then hit First Scan. It should work better that way.
Never would I ever have gotten past Muffet without using cheats. She's way too difficult.