One negative thing I will say about this game is that the hardest difficulty borders on the impossible. In fact, It very way may BE impossible. Enemies that are twice as fast as you, home in on you perfectly, and is nearly impossible to escape from even at full health. part of it is the struggle mechanic. Getting the struggle started is that hardest part.
Yeah, max difficulty is definitely hard and I don't even know if it's possible! But there's ways to increase your chances. Once you know how, it's possible to consistently escape tummies from full health leaving with around 30. It also helps to know ways to juke the wolves, like tricking them into doing a bad jump.
I once almost made it to the end of the first level on max difficulty. I think that stage is definitely possible but I'm a bit unsure about the others. I might tweak things a bit for a future update.