Gosu
Gosu is a 2D game development library for the Ruby and C++ programming languages, available for Mac OS X, Windows, and Linux.
10 Alternatives To Gosu
Adventure Game Studio
Adventure Game Studio provides the tools to make your own adventure, for free!
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AppGameKit
AppGameKit is a game development platform for mobile devices.
BYOND
BYOND is the premier community for making and playing online multiplayer games.
Blacksmith 2D
Black is a highly optimized 2D framework for web, mobile games, and playable ads.
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FlatRedBall
Cross-platofrm 2D game engine using C#, focused on developer productivity, transparency, scalability, and ease of use.
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HaxeFlixel
Create cross-platform games easier and free. All with one codebase.
LITIengine
LITIengine is a free and open source Java 2D Game Engine. It provides all the infrastructure to create tile based 2D games with plain java, be it a platformer or a top-down adventure.
MonoGame
MonoGame is an open source implementation of the Microsoft XNA 4 Framework.
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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!