Epic Games has released an HTML5 version of its Unreal Engine tech demo Epic Citadel. Currently, the project is optimized for Firefox Nightly version 23 or above, so make sure your browser is up to spec before you check it out.

Collaborating with an engineering team at Mozilla, Epic developed a web-capable port of Unreal Engine 3 in just four days. A combination of the JavaScript subset asm.js and Emscripten drove the port's creation, and the result should be playable in any standards-based browser that implements HTML5, WebGL and JavaScript.

While Epic Citadel currently crashes in Chrome, Google's developers are looking into a fix. Internet Explorer does not support current versions of WebGL. Epic Citadel launched as a free download for iOS devices back in 2010, paving the way for Chair's release of the hit Unreal-powered action game Infinity Blade later that year.