Sonic title cards
Sonic games usually show a title card when starting an act. The title card with the stage name shows up, then the game area can be seen, then the title card flies away. In some of the games, this transition is achieved by doing a fade-in effect that only affects the stage itself (but not the title card):
The trick is that the title card uses the common palette while the stage palettes are the ones that get faded in. Objects are not drawn until the fade in happens… yeah, they just let them pop in (if they use the common palette) and hope it doesn't stick out too much (in fact I had to slow down the fading a lot in this GIF to make it obvious).