Amaranthine Voyage: The Tree of Life

This 1st entry in the series is an instant classic and I highly recommend it to fans of the genre. It would appeal most to those who are up for a bit of a challenge.

The story won't wow you, but it's a fun game packed with a lot of content, all of which is original and logical. It features lots of good hidden-object scenes, quite a few puzzles (some of which are quite clever), and delightful full-motion video of characters. The point-and-click adventuring is on the more difficult side, with very little hand-holding, but there's an in-game guide as well as hints if you get stuck. Unfortunately there's no fast travel, so you will have to backtrack quite a bit.

One thing to note is that this is a bit of an older game, so the resolution is quite low. The default aspect ratio might also be wrong (I had to enable "aspect correction" in settings). But despite the low fidelity the drawings are clear and pretty.

Also note that there are in-game achievements, but they are not linked to Steam.