Update 2015-10-21: This is the early 2014 release (called 1.1, which was really v0.9.8), which is sadly not longer actively developed. We still support it as best we can, if you have any questions go here: https://forum.deltaengine.net We are working on v0.9.9+ on internal projects and will release v1.0 later when our own game is released: http://towersgame.net
The Delta Engine is allows you to develop applications and especially games for many different platforms (mobile, tablets, console, PC) completely under Windows with .NET by using your favorite tools.
It is free to use on Windows, Open Source and written in C# (.NET). Supported Frameworks: GLFW, OpenTK, SharpDX, SlimDX, XNA and MonoGame. There is also a native C++ version available at https://github.com/DeltaEngine/DeltaEngineCpp
This release uses NuGet to get all required dependencies, except MonoGame (you can also get the Delta Engine itself via NuGet). Only the .NET Framework 4 Client Profile is required.
We also recommend Visual Studio 2012 or 2013 (e.g. the Express version). For additional tips see: http://deltaengine.net/learn/startingwithcsharp
For details see http://DeltaEngine.net