Application that allows you to add multiple accounts into one apps
Custom launcher for Minecraft to easily manage installations
Community version based on the PCL open source secondary development
Cocos simplifies game creation and distribution with Cocos Creator
A charting and data visualization library for Unity
Open source cross-platform multi-purpose game toolkit
A free/open source client and automation tool for Ragnarok Online
Rcon client for Minecraft
An open source re-implementation of RollerCoaster Tycoon 2
A completely free, open-source, 2D game engine
Free game engine for development of desktop, mobile, and web games
Custom launcher to manage multiple installations of Minecraft at once
A pure Go game engine
Stride (formerly Xenko), a free and open-source cross-platform C# game
Multi-platform Engine for Desktop, XBOX (UWP) and Mobile games
scene-oriented, flexible 3D engine (C++, Python, C#, Java)
Source code repository of the FreeOrion project
Open source library for N64 development
Cross-platform 2D and 3D game engine with modular architecture
A downloadable game for Windows, macOS, and Linux
Open source library for creative expression on the web, desktop, etc.
DRM remover of the SteamStub variants
GLScene Engine for Delphi & C++Builder VCL Windows 32/64
GEDKeeper - opensource and crossplatform genealogy management program
... the open-source glide computer