The following is a list of tools which I’ve found useful when making video game projects

Audacity

An easy to use audio program. I’ve used this to convert MP3 files into OGG format when using RPG Maker MZ.

GNU Image Manipulation Program

I’ve used this for a graphic editing that I’ve done in my RPG Maker projects. It’s good for all versions of RPG Maker, from RPG Maker 2000 to RPG Maker MZ.