HAH! Genesis! Completely forgot about that one as well. Thanks Troop
Yes, the Genesis device can work both ways as stated in the movie. Although it was intended for mass-Terraforming, in the wrong hands it is a weapon utter devastation. however after all's said and done the device would transform the destroyed world into a new one filled with life once more. Although it wasn't successful due to the usage of Protomatter. But that may have been on the large scale as the Genesis cave (the stage 2 test) is still vibrant and alive.