Couples of advice for Hard badge:
1. Don`t waste your money for any other active skills, except basic airstrike.
2. Don`t waste your money for minigun - it`s awfully weak.
3. Missile launcher works best with 30% reloading skill, it is too slow without it.
4. While riding a vehicle, try gathering soldiers, it`s very useful in endless mode, especially before cars riding after enemy airstrike.
5. The skill that enable you to achieve hard badge is called - Future armor, with it you could not be worried too much about your soldiers (for example I make it in endless mode to 3000m. withiut losing any of my soldiers form the beginning.
6. Try position your soldiers at a half of the screen, they will shoot in enemies that you don`t see.
7. Best weapon till rocketlauncher is shotgun - its wide and in good killing.
8. If you have been killed too much in endless mode, train in normal mode, it would be easy, but profit you much.
9. Bla-bla-bla
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