Omega Factor was originally released six months ago in Japan, but the developers have used that time to make numerous improvements to the English-language version. Many stages have a different assortment of enemies, and formerly "empty" levels now have more enemies in them. Some enemies gained additional attacks, including most of the bosses. Graphically speaking, the number of instances of slowdown has been significantly reduced, the color schemes of some enemies have been changed to make them easier to see, and a boss health meter has been added so that players know exactly how much health a boss has left. Lastly, a third difficulty setting has been added and the old difficulty settings have been made tougher to make the English version much less of a cakewalk than the comparatively easy Japanese game. These tweaks and improvements cause Omega Factor to be that much closer to perfection.