Rookfall is one of those games where the objective is to fill the entire grid by swiping a rook as far as it will travel.
You first must choose the starting point.  The red lines are walls that cannot be traversed.
I tackled about 20 of the 5x5 grids.  There are about 100 levels in the 5x5 size. I didn't play any of the 6x6 or 7x7 because those cost money.  And besides, I've done thousands of these over the years via other apps.
I like the graphics.  The rook travels fast.

http://www.rookfall.com/
https://itunes.apple.com/us/app/rookfall-free/id1184528452"mt=8
https://play.google.com/store/apps/details"id=com.ButterGames.RookfallFree

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