Tools I use to make stuff

ClipStudioPaint

2D illustration software with 3D reference object capabilities
Perpetual license (pay once, keep forever)
ClipStudio website

Gimp

Free alternative to CSP
Mainly used for image manipulation and editing like Photoshop
GIMP website

Blender

Free open-source 3D modeling software
Can export to gLTF and OBJ formats that are used by most game engines
Blender website

Godot Engine

Free open-source game engine with 2D and 3D capabilities
Supports multiple programming languages (GDScript, C#, C++ and others via community support)
Godot website

Audacity

Free open-source audio editing and recording software
Audacity website

jsfxr, an 8-bit sound maker

Website for creating free 8bit sound effects w/o AI
JavaScript port of the original sfxr tool by DrPetter
jsfxr website | DrPetter's site

Ezgif, online GIF & image editor

Website for turning videos into Gifs and converting image files into different formats
Ezgif website