FlatRedBall
Cross-platofrm 2D game engine using C#, focused on developer productivity, transparency, scalability, and ease of use.
22 Alternatives To FlatRedBall
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Black is a highly optimized 2D framework for web, mobile games, and playable ads.
Cocos2d-x and Cocos Creator
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Construct 2
Scirra Construct is a 2D game development engine with a focus on building games visually.
LITIengine
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MonoGame
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RPG Maker
Make your own PC game with RPG Maker. Our easy to use tools are simple enough for a child, and powerful enough for a developer. Try it free today!
UDK
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Unity3D
Unity is the ultimate game development platform. Use Unity to build high-quality 3D and 2D games, deploy them across mobile, desktop, VR/AR, consoles or the Web, and connect with loyal and enthusiastic players and customers.
Unreal Engine
Unreal Engine 4 is a suite of integrated tools for game developers to design and build games, simulations, and visualizations.