I finally beat this game and got the card. I am so glad i don't have to play this game anymore. Definitely should not have been selected as a challenge. At times the game laggs and is way to easy through the 1st 14 levels. No doubt that the developer should include a HP meter on both the bosses and the city.
 "Generic Defense Game"){kind=icon}
 "Four Second Frenzy"){kind=icon}
 "B29 Assault"){kind=icon}
 "P.O.D."){kind=icon}