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Free, cross-platform 2D game engine powered by Haxe and OpenFL
Free game engine for development of desktop, mobile, and web games
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Stride (formerly Xenko), a free and open-source cross-platform C# game
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Orx: Portable Game Engine
Game engine supporting many 3D/2D formats and graphic effects
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Entitas is a super fast Entity Component System (ECS) Framework
Engo is an open-source 2D game engine written in Go
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The Atomic Game Engine is a multi-platform 2D and 3D engine
2D physics engine for games
Cross-platform 2D game engine