Loyal Blog Followers know how much I liked Bart Bonte's Factory Balls.   Boo! is Bart's latest and it's a stencil puzzle, just like Factory Balls.
There are only 16 levels. They get pretty hard. But, I've done them all. 
Get in the spirit of the holiday and play this.

https://itunes.apple.com/app/boo-factory-balls-halloween/id1299443361
https://play.google.com/store/apps/details"id=air.com.bartbonte.boo

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