Unity, a development platform for creating multiplatform 3D and 2D games, has today finally been released for Linux as a 951Mb .deb file download. This is an Experimental Build, with future support not yet guaranteed and very much depends on user adoption and feedback.
Today’s build is based off Unity 5.1.0f3 and comes with the ability to export to the following runtimes:
There is a a new section of the forums for you to provide feedback and report issues.