Fun fact, every level forces you to a certain size before you can exit. I didn't want to implement it as a system so we did it in level design instead! You're probably thinking about levels 5 and 6, but you can go to level select and see for yourself, you can't really exit 5 as a kitten. That middle section is intentionally not very hard because we wanted to make sure players have mastered the mechanics before throwing hard levels at them.