Sites include Earth, the Moon, Mars, Venus, Uranus, Neptune, Mimas, Europa, Titan, Umbriel, several large asteroids, and deep space itself! In space, there will be ore in small asteroid belts, but on small planetoids it will be plentiful.
Your battlefield will have an effect on which units you can use in combat as well. Certain units on higher-density planets will not be as effective as on lighter planets. Some will be so inhospitable, you won't be able to use infantry. Plan your strategies to your environment to gain the edge against your targets
