Loyal Blog Follower Daniel contacted me about a month ago about Newton's Cradle Puzzle Game.
 It's a 'minimalist' game. This means that the rules are never explained. Theoretically, I shouldn't describe them, so I won't. I'll just say this: it has mysteriously vanished from the App Store. But it is on Steam - a platform that I've stayed away from.
There are 32 levels and I'm stuck on #19. I think I've tried every permutation of moves!
The graphics are a bit out-dated. But that's not important here. The levels have been designed with utmost care.  I don't know who made it either! He/She/They did a great job.

https://store.steampowered.com/app/1328410/Newtons_Cradle_Puzzle_Game/
https://apps.apple.com/app/newtons-cradle-puzzle-game/id1514440401

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