Thanks! I'll add Trine 3 to the list :D

The Blackwell Epiphany (not part of the Blackwell Bundle) can be added too.

Thank you!

Btw, new GOGMix available with a couple of explanations where they are necessary:
https://www.gog.com/mix/games_with_ingame_achievements

You can add Anna's Quest to the mix. :)

Thank you! Are they "standard" achievements?

I don't exactly know what you mean by "standard" achievements, but I guess so. There's a "Bonus" section in the main menu, and one of the tabs in that section are hidden achievements that are only revealed once you accomplish them (see attached screencap).

Yeah, that's what I mean by "standard" achievements, thanks again for the help! If you read (a few posts earlier) about how games like The Saboteur or Indiana Jones handle "achievements" you'll probably understand why I made that weird question :D

Some achievements in FTL unlock new ships. Haven't seen this mentioned in the gogmix.

Hai ragione, provvedo subito! (You're right, fixed!)
Added!

Reading this I would say "War of the Overworld" can be added as well.

Yup, added

Added Yooka-Laylee which has built-in achievements (the same as GOG Galaxy or Steam, I think)!

Ps: Nex Machina added as well

FYI: i added during Oktober 2017 the following Feature wish:

"add in-game achievements on gamecard"

https://www.gog.com/wishlist/site/add_ingame_achievements_on_gamecard

I appreciate your effort for this Topic.
For me some titles will get much more interesting...;-)

Cheers

I'm glad the thread is of use to someone, feel free to help building the list if there's something missing!

Ps: I don't think they'll ever take into consideration your wish, for various reasons (pushing Galaxy and Galaxy features, avoid confusion between Galaxy achievements and In-game achievements, etc.), but I gave it an upvote nontheless