That's not a bad theory... If it wasn't confirmed that Sand Shower was implemented into a build of the game for testing purposes, which would be...
I've been digging through the Sonic 1 Prototype dumped by drx of Hidden Palace, and I found some weird, glitched lift platform in Star Light Zone...
What do you mean? Mystic Cave is called Dust Hill in MULTIPLE prototypes. And we know the desert level is Sand Shower.
Madness Mountain likely evolved into Dust Hill Zone, when then became Mystic Cave Zone, so I hope that's what you go for.
Mystic Cave is Dust Hill Zone
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