For me it was minesweeper clones. I got frustrated one day and decided to learn how to be good at minesweeper. After beating the medium and large boards a couple times I looked on Steam for minesweeper versions, and turns out there’s a whole genre of clones. Some of them are direct clones of the game, while others are very heavily inspired by minesweeper. The two best I played were Hexcells and Tametsi. Hexcells is stylish and is only hexagons (as opposed to the minesweeper squares), while Tametsi has squares, rectangles, and hexagons and is a lot more barebones. However I found Tametsi to be much harder. There were some levels on there that took me an entire day, and I think there’s like 500 levels.
Sounds like hexagons would be easier as you can only have up to 6 adjacent tiles as opposed to 8 with squares.
Besides that, what do they do differently?
Well hexagons are the bestagons
It has a lot of different mechanics. It’s more of a combination of minesweeper with nonograms (aka picross) where the idea is that there is that you can solve all puzzles without any guessing. Check out the Steam page