ASA: A Space Adventure and its sequel
Catyph: The Kunci Experiment are on sale
on Steam for a combined cost of ~ €10.
They can be bought separately too of-course.
They are sci-fi games in Myst style, i.e. puzzle-based Adventure gaming in first-person.
Reviews on AdventureGamers:
, [url=http://www.adventuregamers.com/articles/view/30652]Catyph. They both scored 4/5.
The developer (basically just one guy) has a channel on YouTube,
Simon Says: Watch! Play! , where he uploads his art and gaming stuff, including trailers of these two games:
Catypth.
Each game also has its own website:
, [url=http://www.theblackcube.fr/catyph.html]Catyph.
Steam even has a demo of the second game,
Catyph, for you to test out.
Even though I truly suck at these kind of games I still really enjoy them. They are my favourite gaming niche alongside sim-racing.
ASA took me at least 20 hours to finish,
Catyph well over 40 hours. Looking at Steam reviews the average seems to be 10 and 30 hours respectively, like I said ... I'm quite bad at these games.
If you decide to take them on, be warned: you need to take notes !
Also, there's no video walkthroughs of ASA. The only guide I could find was in Dutch. However someone at Steam has translated it, it's in the community section should you [inevitably ?] get stuck. Catyph does however have a walkthrough on the tube (in French).