Tips in Pillar Chase 2

Round begins in 3.. 2.. 1.
If you are playing MX and if a survivor uses energy burst, use POW hop because they can't jump while running fast
What happens to monster when you upgrade him to level 100, does he become stronger, or what? (I'm new to Pillar Chase 2 and I don't know much, that's why I'm asking.)

How am I going to buy skins now if the majority of those skins say this?