Alternate Medium: Get 5 gold stars for the first five mission - Difficulty: Look at your save file (1 balloon = easy, 2 balloons = medium, 3 balloons = elite, or just look at your high scores)
You are both wrong- Parachute retrospect and B29 Assault are both very easy :) Battalion: Nemesis, Ether Cannon, Momentum Missile Mayhem, Onslaught and Protector are the hardest imo :(
 "Canabalt"){kind=icon}
 "Bunny Charm"){kind=icon}
 "Warfare: 1917"){kind=icon}
 "Warfare 1944"){kind=icon}
 "Frantic 2"){kind=icon}
 "Another Small Favor"){kind=icon}
 "Balloon Invasion"){kind=icon}
 "Ether Cannon"){kind=icon}
 "GemCraft chapter 0"){kind=icon}
 "Pyro"){kind=icon}
 "colourPod 2: dimensionPod"){kind=icon}
 "This is the Only Level"){kind=icon}