pixeldudesmaker - Simple, web-based pixel art character generator.
Unity - The multiplatform game creation tools for everyone.
Universal LPC Spritesheet Character Generator - Powerful, animated character generator for creating 2D spritesheets
Godot Engine - Feature-packed 2D and 3D open source game engine.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
RPG Character Builder - Create thousands of unique character sprites for your 2D game project - free!