You can make it - Open Source MMORPG Platform
Open game and rendering engine packed into a JavaScript framework
Enables Roblox developers to use professional software tools
Desktop/Android/HTML5/iOS Java game development framework
A simple and easy-to-use library to enjoy videogames programming
Open source library for N64 development
Open source library for creative expression on the web, desktop, etc.
Gideros Release version
CTFs as you need them
Self-hosted CMS platform based on the Laravel PHP Framework
An isometric arcade-style game of skill, puzzles and exploration
Orx: Portable Game Engine
Examples of procedural geometry for Unity3D C#
A simple cross-platform game engine for creating old-school 2D games
Arianne is an engine to develop multiplayer online games like Stendhal
Vivid3D is a C++ IDE/3D engine, with python scripting.
JavaScript framework to build game engines, games, emulators and apps
Ze Text Adventure game Builder : Create as you play !
TX Library is a tiny graphics library for Win32 written in C++.
ReShade is a generic post-processing injector for games and videos.
A free 3D game engine to create games and realtimes scenes for Windows
Vivid3D is an open-source 3D engine with powerful 2D UI.
Cinema Enters Game Console
Sdk library for creating 2048 game in c#.
FreeCS is a free-software reimplementation of Counter-Strike 1.5.