What is really annoying is when you leave the tab in your browser, the game auto pauses and stop playing so you dont get any benefits for browsing the internet while you leave the game going
Easiest way I found to beat the last level was to get 4 attacking fortress, than you start getting the small planets to get about 450 untis and go for the mid all at once
 "Idle Empire 2"){kind=icon}
 "Solarmax 2"){kind=icon}
 "Mighty Knight"){kind=icon}
 "Dawn of the Dragons"){kind=icon}
 "Infectonator 2"){kind=icon}