I love how this game worked. It's fun at the beginning, the upgrades don't come too slowly or too fast, And its easy enough to work through the first 14 levels, then grinding to actually be able to beat a "final" boss on the 15th is rewarding, and doesn't take too long. The boss difficulty jump was unexpected, but for once, it made sense. I mean, it's the final boss: most games simply make something the same as the rest, or a pushover. The difficulty was just right here.
You get one star once you reach level 100, you then go back to level 1. Then, when you get all the way back to 110, you get star #2, then you restart again. Then 120 = Star #3, restart. 130 = #4, 140 = #5, 150 = #6, then you go on forever.
 "Katwalk"){kind=icon}
 "Whiteboard Tower Defense"){kind=icon}
 "Boss Battle"){kind=icon}
 "Tesla Death Ray"){kind=icon}
 "Notebook Wars"){kind=icon}
 "Heir"){kind=icon}
 "ImmorTall"){kind=icon}
 "A Knight's Story 2"){kind=icon}
 "A Knight's Story"){kind=icon}
 "Endless Migration"){kind=icon}
 "Infectonator : Christmas Edition"){kind=icon}