Duality 3.0 Open Source 2D C# Game Engine Updated
Duality is a criminally underrated open source 2D game engine, that just received a major update that includes a completely rewritten renderer.
Duality is MIT licensed, C# based 2D component based game engine with a complete Unity-like game editing environment. The only real negative is that it is Windows only, although based on OpenTK, so you should easily be able to port your game to other environments.
Links
https://www.gamefromscratch.com/post/2018/12/08/Duality-Game-Engine-Releases-Version-30.aspx
https://docs.duality2d.net/pages/v3/Changelog.html
https://www.gamefromscratch.com/post/2015/11/03/A-Closer-Look-at-the-Duality-Engine.aspx
https://github.com/AdamsLair/duality
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