How to save your game in New Super Mario Bros. U Deluxe
As you progress through New Super Mario Bros. U Deluxe, certain levels could cause you to get pretty frustrated and make you want to leave the game for a bit to cool off.
As you try to look for a save option so you don't lose all your progress, however, you might not find exactly what you're looking for.
There actually isn't a way to properly "save" the game when you want to keep your progress after you get to a certain point. The only way to save your progress is to beat one of the many castles scattered across the world. Once completed, you can finally save your game.
There is an option, however, called "Quick Save," which saves your progress up until a point in the game, but it's only temporary. You can choose this option by opening up the menu out of a level and clicking "Quick Save." It's the option with the large red balloon.
Once you reload the save file where the Quick Save occurred, you'll need to keep quick saving to keep your progress indefinitely before you reach an actual save point.
If you turn the system off or close the game without Quick Sav, you'll be sent back to the previous actual save you did—which means you could lose tons of progress that you made through difficult levels.