Unity

Unity is a cross-platform game engine developed by Unity Technologies, first announced and released in June 2005 at Apple Inc.'s Worldwide Developers Conference as a Mac OS X-exclusive game engine. The engine has since been gradually extended to support a variety of desktop, mobile, console and virtual reality platforms. It is particularly popular for iOS and Android mobile game development and used for games such as Pokemon Go, Monument Valley, Call of Duty: Mobile, Beat Saber and Cuphead.[4] It is cited to be easy to use for beginner developers and is popular for Indie game development http://en.wikipedia.org/wiki/Unity_(game_engine)

Game Engine http://unity3d.com/, also for Virtual Reality

basis for Atmosphir and other game environments - http://unity3d.com/gallery/game-list/

Can deploy as Fat Client or WebApp (well, with Web Browser PlugIn) or Mobile (IPhone and Android)

Unity supports three Scripting Language-s: JavaScript, C Sharp, and a dialect of Python called Boo. All three are equally fast and interoperate. All three can use the underlying DotNet libraries which support databases, regular expressions, XML, file access and networking.

• Arcadia is the integration of the Clojure programming language and the Unity3D game engine. It brings a live coded, functional, dynamic Lisp to the industry standard cross-platform game development tool. Mar'2021 update: no activity in a whole year.