Course Theme

A Course Theme is an option you can choose in the Edit Mode interface when creating a Course in an Area or Subarea, meaning a level can support up to 2 Course Themes. For the most part, Course Themes are purely aesthetic but there are some Course Themes that have unique features and interactions. In Super Mario Maker and Super Mario Maker for Nintendo 3DS there are only 6 Course Themes, those being Ground, Underground, Underwater, Ghost House, Castle and Airship. In Super Mario Maker 2 there are 10, adding the Forest, Sky, Desert and Snow Course Theme.

A Course Theme will have a piece of music, tileset and background associated with them likely coming from the Game Style's respective source game. All Course Themes can be used in any Game Style.

Night Mode
Night Mode is a feature in Super Mario Maker 2. To unlock it, you must place the Angry Sun in your level and turn it into the Moon. Upon doing this, your Area/Subarea will enter Night Mode and in the Course Theme selection there will be an addition to the UI that can change it without having to follow the previous method.

Enabling Night Mode will do a lot of things. Most importantly, though, it will add some kind of mechanic based on what Course Theme you're using, as well as changing the appearance of your Course Theme to be at night. It will also replace the music track with a Celesta cover of the Course Theme's respective musical track. Enabling Night Mode on some Course Themes will also change the tileset too. Night Mode will not overwrite Course Theme mechanics unique to its Course Theme unless specified in the table.

Night Mode is available in all Game Styles except Super Mario 3D World.

For more detailed information, images and details, check out each Course Theme's respective pages.

Trivia

 * Every Course Theme has appeared in at least two of the Game Styles' respective source game.
 * The first Course Theme showed off at E3 2014 was the Ground Theme, in the Super Mario Bros. and New Super Mario Bros. U Game Style.
 * The SMB ground style looked different. The background had a grid and the elements had gradients. Also, there were more color in the Ground background. This was fixed in 2015.
 * In any of the retro Game Styles, enabling Night Mode might let you see Undo Dog flying on a rocket if you're high up enough in a level.