Just like the old fashioned game except not really! If i remember the 'classic version' the invaders get faster and the shields disappear when they get too low. Too easy and becomes boring
Apparently 31 people have cleared all achievements in 1 day. Clearly impossible since you can't procede to the next height until all achievements have been completed from the previous height
 "Sierra 7"){kind=icon}
 "Space Invaders"){kind=icon}
 "Learn to Fly"){kind=icon}