Got up to challenge 13. The whole thing is based more on the luck of the cards that you get than strategy. No wonder that achievement is impossible. It's a great game, but these challenges are way too frustrating.
Pretty decent game. you'll probably have to grind for resources by replaying levels at first, but once you've unlocked the Tor and purchased its upgrades along with archer upgrades, the game becomes easy.
An improvement over your past version, but still needs work.
Sounds like you added sounds from Medal of Honor: Allied Assault in the background. That doesn't quite work since that game took place in the European Theater, and you can hear German words in the background. Just a small detail though.