UNDERTALE: How to Change Fun Value

Preparation

Backup Your Data

Before changing the Fun Value, make sure to backup your Undertale data. This is a precaution in case the data gets corrupted when changing the Fun Value.

How to Change the Fun Value

Opening the AppData Folder

If the AppData folder is not located within the Users folder, it may be set as a hidden folder. In that case, go to the View tab and check the Hidden Files option to see if the AppData folder is present.

Opening the UNDERTALE Folder

Once you have opened the Local folder, navigate to the UNDERTALE folder. It is recommended to make a backup copy of the folder as a precaution.

Modifying the Fun Value Number

When you open undertale.ini with Notepad, you will find an entry called "fun". Modify the number (shown as 57 in the image above) to the desired value.

Changing Line 36 of file0 to Match the "fun" Number

When you open file0 with Notepad, you will see a list of numbers arranged vertically. Counting from the name section, change the number on line 36 to match the desired fun value. Once you do this, the fun value will be successfully changed.

What is the Fun Value?

A Numerical Value that Determines Hidden Events

The Fun Value refers to a numerical value that determines the occurrence of hidden events within Undertale. It is randomly set when starting the game, and there are hidden events that only occur at specific values.

Can only be Checked on the PC Version

The Fun Value can only be checked and modified on the PC version, and it cannot be done on the PS4 or Switch versions. However, even though it cannot be checked, hidden events themselves occur on any platform, albeit with a low probability.

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