This is a surprisingly good Twine game from Spring Thing a few years back. I say surprisingly, because I never hear anyone talk about it.
It uses graphics and background colors to distinguish between two different worlds: one, a porpentine-like world with beings of slime and technology, and the other the human world, where a father is struggling with mental illness.
It has puzzles; at one point, there is a long sequence involving the food chain. I found bits of this fiddly, but interesting enough that I was happy when it was done.
The overall storyline was great, and that's what I like best about games. So I recommend this one.