please increase the amount of blood you get, I finished all the demo levels way before maxing the skill tree, it took an extra ten rounds to get it maxed. Please increase the growth speed on the last level, that would make it more difficult to complete and easier to farm, also kinda funny how the flesh doesn't even hurt you, you just die of O2 loss every time. My best run gave me 952 blood, but those runs take so long when you're trying to maximize gain.