Epic has teamed up with Mozilla to bring Unreal Engine 3 to the web with Firefox, plug-in free. The announcement came during the Game Developers Conference where Mozilla showed Unreal Tournament and the Citadel demo running natively in the browser.

Surprisingly enough, Mozilla's engineering director and the inventor of WebGL Vladimir Vukicevic said it only took four days to port the entire Unreal 3 Engine to the web as only small adjustments were needed.

Support for the engine will also be coming to Mozilla's mobile browser for Android and naturally, Firefox OS. There is a bit of a performance hit as games are expected to run within 2x of native performance but considering that something like this wasn't even conceivable just a few years ago, it's rather impressive even if it isn't as fast as native.

If you recall, this isn't the first time we've seen Epic's Unreal Engine 3 on the web. Back in October 2011, the company announced support for Adobe Flash which allowed a number of titles to be played within browsers via social networking sites. Since then, of course, Flash has fallen to the wayside which likely prompted Epic to reevaluate their web presence and ultimately elect to work with Mozilla.

We are told that a demo will be available in the coming weeks but in the meantime, interested parties are urged to check out Mozilla's BananaBread demo that's works with the latest Firefox Nightly.