Minimap changes
 

When you go through the tunnel linking the Underground Lake and the Zormite Castle, your minimap stays as the main overworld one while you're in the Underground Lake. It's not so bad because you can just go a couple screens southwest to an alternate entrance to the underground lake...but when you go the other way through the tunnel, your minimap stays as the Underground Lake one, so if you want the right minimap you have to go the long way :(