Today I found: Bastard Tetris
This, known as bastet to its friends, has been around since at least 2005. I heard of it today. It's a variety of Tetris, but one that will always queue up the optimally worst next piece. ("So kinda like normal Tetris then", I thought.) And there's a devilish mode in which it will not tell you what piece is up next either. That one was too hardcore even for me.
It's available in the Ubuntu package repositories as bastet, and on Homebrew for the Mac, and apparently there is even a Windows version.
You may have heard of the Tetris effect; I wonder what damage this hilariously evil variant could do if you played it enough. The stuff of literal nightmares?
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