What were your favorite steam games to do all achievements in?

Today I've got my last two achievements for Attack of the Earthlings: You're Pretty Good At This and You Absolute Madman!

I had a blast and it was really fun game to play and to do all the achievements. Happy birthday, Carlos. :-D

I always say in these topics that Brothers: A Tale of Two Sons has the best-implemented achievement system. You see, it is completely possible to not earn any while you progress through the game story (making you look like you just idled) but to earn some, you have to stray away from the story path and do some side objectives (that are nowhere marked) and you learn more about the lore of the game and the world in it. It's really amazing

Heroine's Quest, an amazing (and free) point and click / RPG hybrid. Back when I 100%'d it there weren't a lot of guides for it, and figuring out how to do the various perfect runs was both challenging and fun.

Oh and also Grimrock 2, I absolutely loved the level design in that one and how open it was to sequence breaking.

Binding of Isaac
Terraria

I think I'd have to say Rain World.
I enjoyed it so much that I actually played through Hard Mode even after I'd completed all of the achievements, which is super rare for me. Most games I'm just done with after beating and completing.

Hero of the Kingdom 1 & 2. I also 100%d Hero of the Kingdom 3, but 3's thing where instead of having a finite number of eggs/mushrooms/etc, the resources respawned when you did enough other stuff was both nice and eh....

Enter the Gungeon and Metal Gear Solid V: The Phantom Pain, absolutely loved this two games.

Half Life 2 and Dishonored

Europe Universalis IV. Very hard to master but strategy games are my favorite since Civilization 1 and started grand strategy games with EU2 around 20? years ago. Lost perfection since then, becuase i want to play other games too and stopped purchasing DLCs.

Sleeping Dogs.Loved the game immensely,I replay it from time to time just for the hell of it.Only issue for 100% completion was that connecting to Square Enix servers was a nightmare,and it became impossible a few months after release,locking you out of the achievements for bronze,silver and gold challenges so i had to add those using SAM after achieving them.Once i get through some of my backlog i will 100% the definitive edition as well.

The Binding of Isaac, easily. Tons of fun

Resident Evil 4 was my favorite to do all achievements. At the time i bought it on Steam i had finished it a few times on the PS4 and 1st PC version.

Minoria is the only one where I got all cheevos, so that one. Good game, and achievments aren't some dumb bullshit, like they are in most games.

Dead Synchronicity: Tomorrow Comes Today. (I loved the achievements because you got them for doing things incorrectly or what would be considered at the vert least, "crude", "immoral", and "rude", and they're all named after books and horror films)
CARRION (was just super fun being an amorphous blob that can destroy everything.)
Little Misfortune (I enjoyed this way more than I thought I would. great, emotional story, with funny/heart warming achievements.)

Bastion and Transistor
2 play throughs of the games to nab them all

dungeons 3
all the achievements were for "just" beating the missions on hard.

FTL

They added achievements several years after the game release (after I already had a 100+ hours into it), and the achievements drug me back in to get what I missed. I still play FTL every now and then between games to knock out those dirty rebels.

dont really know, but most HOG games are easy enough for achievement

Did someone already say Reventure? :D