In 2010, Epic Games released the Epic Citadel tech demo to show off what the Unreal Engine could do on an iPhone. Now, it's re-released that same demo running in a web browser on Flash 11, for you to have a look yourself. Epic also showed off Unreal Tournament 3 and Dungeon Defenders running in Flash, with only a moderate performance hit.

Head on over to the Unreal Engine site to visit Epic Citadel. You may need to install the test version of Flash Player 11.2, if you don't have it already.

"For the same piece of content there is definitely a penalty on Flash in terms of CPU performance," Epic's Mark Rein told our roving reporter Andrew at GDC, but the Flash version of Unreal Engine 3 still runs around 70% as fast as the regular. Given how much more portable and accessible it is--the Flash Dungeon Defenders only has a 15MB initial download--it's a reasonable hit, and Rein noted he can still run DD on his lowly Macbook Air.

Epic again showed the Unreal Tournament 3 Flash demo it used to unveil Flash support, but has no plans to release it. However, Rein told us, "We want to do the Samaritan demo on Flash."

Epic Citadel isn't simply a fancy display of something Epic might do--Flash is now an official supported platform of Unreal Engine, thanks to Flash 11's GPU-accelerated 3D. It should almost certainly be a standard feature of Unreal Engine 4, which Epic plans to unveil this year.

As befits the Game Developers Conference, Epic also whipped together a trailer showing off the various shiny features the Unreal Engine 3 has to offer developers in 2012: