I meant that maybe you could make portals as part of the game - bosses generate them and everything goes through. I think it would make the dodging way more interacting.
Hm, poison? I understand now what you mean but makes no sense in terms of WAKER. I'd suggest it to be energy that gets lost when the boss is shooting but it's not a physical overworld, is it?
Or actually, how much of the game will depend of one's own interpritation? I'm asking because another great thing about Undertale I haven't mentioned yet is that once you start theorizing and reading other's theories you have the feeling like many things are left up to your own interpritation but the deeper you get the more you realize how perfect (almost) everything ties together. That's why I'm trying to think of some logical explanations for how this game works but every update makes it more difficult.