The one thing that I’ve really wondered about since I first read Alys is what effect the ability for dreamers and changelings to effect themselves has on the real world. My main thought being, if while in Terra Mirum Alys decided to make herself slightly taller or changed her hair colour would those changes be maintained when she returned to earth?
For Dreamers, nope. Same as when you wake up from your dream, you cannot in fact fly. They only have a control over Terra Mirum, not any other world. This control may also potentially be tampered with/altered/hindered. But that’s another story. ;P
Changelings, however, depending on their heritage MIGHT be another story.