Incredible entry, I loved this!
I think that the core idea of the puzzle is clever - ride animals to reach the exit - and perfectly fits the "parasite" theme. But on top of that, you also built a solid and satisfying gameplay! More specifically, the levels are greatly designed, and the new mechanics are always well introduced, in a way that doesn't overwhelm the player with options, but at the same time leaves them free to reason and think. This is an amazing work of game design, good job and congrats!
Speaking of negative aspects... I GOT STUCK :( I managed to reach the level you see in the attached screenshot (of which I don't know the number), and when the gorilla was facing the hedge, I had this kind of intrusive though:
...what if I was able to break the hedge?
So I pressed SPACE, and I broke the game instead, LOL. No movement, no restarting, everything froze.
I know I've been pretty stupid and greedy, 'cause I had the solution in my mind and I could have just flown to the exit. I could have played the game, instead of beta-testing it, you know. But well, at least I hope that this bug report could be useful to you.
Besides all my failures, I can assure you that I had a lot of fun with your game, so thanks and congrats for the amazing submission! As soon as I'm free for another half hour (which is approximately the time that required me to reach the cursed level), I'll definitely retry it! ^^"