This game has partially hidden difficulties, which you may like to play or speedrun. This is a quick guide on how to unlock those difficulties.

First, go to the Options menu for the Virtual Circuit Mode. Difficulty is the first setting, on the top. The first time you ever boot the game, you should be on "Normal" difficulty by default. If you press left twice, you will find yourself on "Easy." While on "Easy", if you press left twenty times in a row, you will see the difficulty "Very Easy" appear. Once that happens, lock in your difficulty by pressing A to save your options, and you are ready to play.

You can unlock "Very Hard" in a similar manner. From "Normal", press right twice to reach "Hard" difficulty. While on "Hard", press right twenty times to make "Very Hard" appear. Once that happens, lock in your difficulty by pressing A to save your options, and you are ready to play.

If you unselect one of these hidden difficulties, it seems to become unavailable afterwards. Simply follow the steps above whenever you would like to reselect "Very Easy" or "Very Hard."

This video shows me unlocking both hidden difficulties, first unlocking "Very Easy" by pressing left twenty times, and then unlocking "Very Hard" by pressing right twenty times: