Fascinating. Recall how the winter level in Sonic 2 had Christmas trees (although the art here just shows trees. They don't seem decorated or anything...). Also notice how similar to Mushroom Hill having a weather changing machine, Ice Cap has a snow machine. This implies Ice Cap originally wasn't a natural snowy mountain, but rather artificially covered in ice and snow by a machine Eggman made, and this explains why Angel Island doesn't seem to have any snow or ice on its mountains when you see the whole thing. Because by the end of the game, Sonic has destroyed it. This makes me wonder even more about that one piece of art... Also recall how in Sonic 2, the winter level was going to be a "ruined" version of the desert level. Perhaps this would've been caused by a weather machine, and this cut concept was going to make its way into Sonic 3, but it got scrapped and instead MHZ is the only one with a weather-changing machine.