Steep Mountain - Climax of Terror/Fiery Volcano/Freezing Glacier/Stormy Summit/Slimy Pinnacle/Gremlin Watchtower/Wild Meridian/Poisonious Peak

The map would consist of one passage going up, with the exit at the top. There would be many part buttons along the way, triggering monsters, etc. It would be like a reverse Spiral Fortress going up and inward. It would give the impression that you are climbing a mountain.

Deep Cavern - Crystal Cave/Cold Cavern/Wistful Winds

The map would consist of going down and down into a cave of freezing ice, with a sort of boss at the bottom. There would be mirror that would reflect bullets back at you.