I don&#x27;t think there are a huge number of Steam games running on .NET, but the number might be increasing due to the rise of Unity.<p>Many, many games are written in C++ and require reasonable porting efforts to get to Linux support. Someone like Ryan C Gordon (icculus) is much better qualified to comment on that, though.<p>I doubt Microsoft would ever port DirectX to Linux, but then again I doubted they&#x27;d do that with .NET, and look where we are.<p>The DirectX-&gt;Wine code works pretty well, but it&#x27;s always going to be behind the state of the art.