We* need to solve this mystery!
*probably not going to be me
I beat Atomic Robo-Kid Special today after working on it for a couple days, and I also noticed that Act 21 seemed to change up between playthroughs. Since one or two of the earlier Acts have multiple exits, I'm guessing it may have something to do with that.
BTW I also like this game a lot, though the final boss is aggravating and a couple stage enemies are too.
I don't think I would have given this game a third or fourth chance to win my heart, but sunbeam_paul here had such love for it that I gave the damn game another chance and realized it does, indeed, have some charm to it.
However, I have not beaten it. Not at all. But this thread reminded me that I have to add "Atomic Robot Kid" to my "next up" pool of games.