I resist puzzle games, but it's always a delight when I cave and give myself over to them. Today I've been lost in Hanano Puzzle [official site], a game about touching blocks to flowers to make new flowers grow. It offers repeated revelation in the way the best puzzle games do, by having levels that look impossible until you discover some facet of the existing rules you hadn't previously encountered. It's by the same developer as Jelly No Puzzle, which received a lot of attention and John adored back in 2013. It's free; you could be playing it already.
Each level is a single screen containing some coloured blocks and coloured flowers. Touch a block to a flower of the same colour, and a flower will sprout from the block. You can slide blocks left or right, or swap their positions with another block to the left or right. To begin with, that's it, though you discover new rules with each new level: flowers grow out of different sides of blocks, as indicated by an arrow; flowers can't grow if their path is blocked; there are grey blocks which can be moved but don't sprout flowers; and so on.
If you've ever played Sokoban or a similar game, you can already imagine the thought processes involved. Your mind ticks from "how the heck is that possible?" to "this is definitely impossible " to "oh, can I move this one red block over there?". Plans are formed, lead to dead ends, new ideas are conceived and tested, until the eureka moment hits. You're going to want to make liberal use of the restart button, and there's a one-step rewind button that's useful too when you mis-click or instantly realise your mistake.
There's also a sequel, which I haven't played but which is pay-what-you-want on Itch.io. And if you play the original, mute the music immediately - it is awful and maddening.