I would both like them to put a badge on this and also not. I don't know if I can to subject myself to that level of intense (strangely wonderful) self-loathing again.
For those who think 16 is impossible (and future ones too, because I felt exactly the same way as you!) later on ORDER of placement matters as much as where you place it.
I think Mr. Bookworm learned a different version of checkers than I did. I think I played a variation like this game, but these aren't the 'original' rules.
There is a level progression meter. In the background there is a faint gray line that progresses from left to right. When it reaches the right side, you're done. It's hard to see, and could be brighter, but it's there.
To get to the 'normal version' (without having to google it.) Take Mr. Sling and have him connect all four dots on the opening menu. This will open a warp to a link to Sling and Sling Fire.
 "Min Hero: Tower of Sages"){kind=icon}
 "Give Up"){kind=icon}
 "Isoball 3"){kind=icon}
 "GemCraft chapter 0"){kind=icon}
 "Super Karoshi"){kind=icon}
 "Checkers"){kind=icon}
 "Orb Blaster"){kind=icon}
 "Original Blast Billiards 2008!"){kind=icon}
 "Breach"){kind=icon}
 "Luna Park: Volume I"){kind=icon}
 "Sling Junior"){kind=icon}