I saw the commentaries and i agree that the game, beyond simple and fast (as the game already says), the history, the architecture and the sound is very motivating for playing these. By the way, there are more difficult games which don't have any badges, like Mushroom Madness.
The game is very hard. You can't die, actually, to receive the impossible badge, you can't take ANT DAMAGE. I tried it for a month, but it tired me. Cheat Engine for the badge is an option.
This game is one of the best strategy and tower defense games with elements of RPG. It's the same level of Epic War. And i finish the game with 100%, all buildings, recruit all units and the wall and the catapult don't have any damage on the final wave of every stage (this is hard, but i did it).
The first 2 badges, don't need to say, easy. The hard badge is more harder than impossible. The impossible you can make the tower using the 2 spaces in the both sides where there's no ground with the red, orange and blue blocks. This way, it's more easy, guarantee that the tower will not fall. The hard, however, it's more luck. There is a video on youtube showing a quick way to do it. But it's hard anyway.
Too Easy. There's a bug which happens to me. When i Was Obama, i fought McCain and only him! Sarah doesn't appear! Then, the second time she appears. But with McCain is more difficult to end because Sarah is more weak and they don't have strong powers as Obama and Biden.