Reverse engineering Unity game from .exe file and _Data folder

Generally it’s not possible. Data is lost (variable names, comments, etc) during the packaging process. Also many asset conversions result in irretrievable data loss.

You might find more people who do this sort of thing on the modding forums to perhaps get you bits and bobs of the project out, but nobody here really hassles with that stuff.

Please consider using source control in order to guard and protect your hard-earned work.

Personally I use git because it is free and there are tons of tutorials out there to help you set it up.

Here’s how I use git in one of my games, Jetpack Kurt:

Using fine-grained source control as you work to refine your engineering:

Share/Sharing source code between projects:

Setting up the right .gitignore file: