For adding a new Difficulty you will need the Source Code

On this Example, i will be adding a new difficulty called "Crazy", all charts for this difficulty should end with "-crazy".

Adding to the list

This is probably the easiest part. Our difficulty will be called Crazy, and the chart suffix will be -crazy

Open CoolUtil.hx inside source/, right at the start, you will see this array:

So... add your new difficulty to it, like this.

Files needed

You will need the difficulty image for the Story mode menu, and you're also gonna have to do the Crazy difficulty chart to all songs. Here's my Crazy difficulty image for an example:

Put this image inside assets/preload/images/menudifficulties/ with it being named crazy.png and we're ready to go! If you've done everything alright, it should be in and working properly!