Might and Magic 2 (which is included as part of Might & Magic 6) just for the nostalgia of being the first computer game I played. I still love its cartoony graphics and stacks of monsters.

Lands of Lore 1, Ultima Underworld 1 & 2, Eye of the Beholder, and the other Might & Magic games would be next.

The Elder Scrolls IV: Oblivion. I need to get it on here someday but yeah, I'd say it's pretty evenly in competition with Fallout 4 as my favorite game of all time.

Sid Meier's Alpha Centauri. Lots of great memories, I can still feel some of the excitement I had for this game as a kid. It still plays really well. To me it's the ultimate epic sci-fi adventure.

Has to be Maniac Mansion.
https://www.gog.com/game/maniac_mansion

Probably Terraria but it might change if I play more different games when I beat games I am playing rn

The Witcher Trilogy.

Loop Hero, it is just so relaxing.

I'm impressed whenever people can name one single favorite game (or movie, or book) assuming they played any significant number of them. As someone above said already, I too would have problem with compiling TOP 50 list.

Fallout: New Vegas. Once I realized it was here, I got back into PC gaming after being away for like a decade and a half, so disgusted at how many big PC releases over the years were released (mainly on Scheme) in DRM form, which to me is unplayable! I was so glad to find New Vegas, which I had first played on console and fell in love with, in a DRM-free offline installer available for purchase here.

Honorable mention to The Age of Decadence, a true role-playing game that I can't say enough good things about.

Right now, it's probably Day of the Tentacle.

Way too many to even remember, but some of the best I can think off the top of my head would have to be:

- Grim Fandango
- Day of the Tentacle
- Nox
- Broken Sword: The Shadow of the Templars
- Broken Sword II: The Smoking Mirror
- Primordia
- Saints Row IV
- The Suffering
- The Suffering: Ties That Bind
- Metal Gear Solid
- Metal Gear Solid 2
- Psychonauts
- Psychonauts 2
- DOOM II
- Fallout 2
- Arcanum: Of Steamworks and Magick Obscura
- Dear Esther
- What Remains of Edith Finch
- Batman: Arkham City
- Outlaws

And even though they're quite recent, I'd like to add

- Eastward and
- Death's Door

to this list, because I hadn't played such great, fun games in years.

[EDIT] Ongoing EDIT because, obviously, as soon as I click "Post my message" I notice I forgot to mention a game.

[EDIT 2] Added GOG links to the games I listed.

Stronghold Crusader HD, Mafia and Swat 4

"Original Broken Sword Game (English)", even though technically speaking it is not available as a GOG game, as it's a bonus of the DC version and not an individual title in the catalogue.

If we talk about what title in the catalogue is my favourite, then I really don't know. Let's say "Leisure Suit Larry" which includes most of those original Larry games in a single purchase.

Prey tell, what is your favorite GOG game?