Just upgrade bombs to max, price, range, damage. Then put super tower to the end of route, and fast release all units to the field (all levels), find nice corner. shift+click on small bomb, and just click, click, click. All levels to expert in half of second hour.
 "Give Up, Robot"){kind=icon}
 "ClueSweeper"){kind=icon}
 "mini Tower Defence (mTD)"){kind=icon}
 "Obama Punch Out Xtreme!"){kind=icon}