Crystal Nightmare is an online multiplayer tower defense game that I built in highschool using Unity3D with my friends at CodeDay Portland.
I wanted to extend support to OSX and Linux, but it turns that out a lot of the Unity3D features that were used to build the game is now obsolete. If I have time sometime (looking increasingly unlikely!), I'll try to fix all the issues and extend support.
I'll eventually write an article explaining the details of this game and what led me to make this game.