The 3D Combat Shooter “Metal Sun” is right now under production by  Silver Machine Games and will be released anytime soon. The game is a 3D combat fight simulator which is based on the 80s classic game Defender

From what i have seen on the gameplay video and screenshots, you can move free in completely 3D environment and the goal is to defend a small group of people  from some bad ass aliens.

This title looks definitely promising,  as well the developers have some big plans for the iPhone 3Gs

The 3GS graphics capabilities are amazing and we’re currently in the process of a major upgrade to the VIVID rendering system (our internal engine) to support it. Some of the stuff we’ve currently got in alpha test look better than some PS3 games I’ve seen – particularly when it comes to destructibility; we’ve got an entire city on one 3GS device that comes apart down almost to the individual brick level. Smoke, debris, flames and pieces of skyscrapers falling down so realistic it looks more like a movie than a game. The 3GS is just that powerful!

For this first release though Metal Sun was designed to run and look good on a standard iPhone – indeed, until things start exploding it actually runs at 50 FPS on a 2G touch! For the next release though it’ll detect if a 3GS is present and if so will enhance the display considerably! And then some.