Fenrisus's Stars
Librelancer/Librelancer
A re-implementation of Freelancer
MonoGame/MonoGame
One framework for creating powerful cross-platform games.
tanis2000/Overlap2D-NET-Runtime
Overlap2D C# runtime
Dahrkael/PhysFS-AES
PhysFS 2.0.2 with AES encryption support
xoreos/xoreos
A reimplementation of BioWare's Aurora engine (and derivatives). Pre-pre-alpha :P
Ezzz-dev/OTSharp
Tibia Game server developed in C# to use with Tibia 7.6