Tip: If you give a Muncher tile custom graphics, it will still act like a coin when a silver P-switch is active, whether it looks like a coin or not. So make sure to use ExAnimation if there's a silver P-switch in the area.
The short and calm theme from Yume Nikki's Snow World aka Snow Valley. Would work well on, who guessed it, snow themed Overworlds. Although maybe this would work for Space Overworlds too.
Special thanks to LHB and Pinci for helping me out with this port.