It is, as it states, 
mini ten pin bowling where all the parts pack into the unit (if you only pick one launcher type) and the bottom half slides forward to give you access to all the pins once you have knocked 'em down.

This standard version fits on a 250mm bed diagonally. 
The Base_180.stl & Top_180.stl fit on a 180mm bed diagonally. All other parts are shared.
 

There are three turnable launchers to choose from: launcher A is the standard, launcher B provides a little guidance and launcher C gives the biggest helping hand.

The ten pins all printed (two colour) without a brim on my smooth plate, but as they have a small footprint, you might want to employ a brim.

The two ball halves and internal cube fit together tightly. That's on purpose, as then you don't need glue, but if they turn out to be too tight, just run your nail (or a nail file, sandpaper etc) along the cubes edges and it will snap in.
Also a good marble will fit the bill nicely if you happen to have one handy.

All parts printed with basic pla, 0.2 layer height, 2 walls, 3 top & bottom layers with a 5% rectilinear infill... Till golden brown (nope, just kidding :)

Fast lane through a hurricane, open road and I'm ready to roll...

--PATREON & PATREON SHOP.
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