if any body have or earned SPEC OPS COMMANDO OR SPEC OPS COYOTE ARTILLERY, just fight with these units, and when your battle will end, and where it ask you to buy for empire points, there in the amount of empire points is 0. so you can buy these two units for 0 empire points. fight as much as you can to buy more and more. i got 100 units of both, seriously legally not with hack..try it before zynga fixes this bug. goodluck