One of the rarest achievements I have is not at all difficult. It's not even trying to be. It's on Street Fighter 5 for saving 30 replays. Apparently nobody does that?

Video game news oriented community. No NanoUFO is not a bot :)
Posts.
Comments.
My goal is just to have a community where people can go and see what new game news is out for the day and comment on it.
Other communities:
One of the rarest achievements I have is not at all difficult. It's not even trying to be. It's on Street Fighter 5 for saving 30 replays. Apparently nobody does that?

Back when RDR2 was fresh on PC, dinked around once with the death match modes and never again lol.

My rarest achievement is from The Long Dark (Finely Tuned) at 0.1%. But that's because not many people played the last episode when it came out.
My most memorable is from Titanfall 2 (...Becomes the Master) Place in the top 3 of the Gauntlet scoreboard. That one is at 2.9%
Nice, i didn't try to get Finely Tuned mainly because i haven't bothered with a second chapter 5 playthrough. Mine is the 1000 day Interloper one at 0.2%, took me two years haha

There’s a lot of achievements on this game that barely anyone has

Definitely not as rare as most of y'all and probably only as rare as it is because of how many millions of people play stardew valley without ever even trying the arcade machines.
0.4% Pillars of Eternity 1: No Rest for the Pro. Complete the game with fewer than 10 rests.
I got this through sheer indecisiveness on my first playthrough.

The cactus simulator one. That was a lot of standing.
Napoleon Total War. Not sure if I was achievement hunting or not but it sounds fun.

Apparently, completely finishing any Lego game (I have, at this point, completed 6 of them).
Is there an easy way to find out without using third party websites?
Set the "showcase" at the top of your profile to "Rarest Achievement Showcase". I'm not sure how else to see it natively.
In your steam profile settings there's a tab named Showcase Manager in which you can choose to display the Rarest Achievement Showcase on your profile page, it will show your rarest achievements on your profile
It's not an achievement, but this is pretty rare

This was my senior year of college. I would stay up all night playing Counterstrike and Day of Defeat.

21 here, I too am old as hell
I don't meet many people like you anymore.

Shit, 17 days apart lol. Did you also get a copy of Half-Life 2 for Christmas?

I think I bought the Orange Box? Or HL2 for myself.
damn, y'all, how big were the dinos back then ?
Big enough to screw up the platters on my hard drive when they stomped by!
My top 20 rarest achievements according to steamvault were all dirt rally ones about beating easy stage times...
Not many people played dirt too seriously it seems 😄
Not as rare as some others, but takes a little while to achieve:

Still working on Super Go Outside
What about the inverse?
I got Satisfactory before the 1.0 release. I played most of the game before achievements were added. Now the achievement for "reaching the credits" is achieved but "finish the tutorial" is still waiting to be done.
Heart of the machine, 0.4%

Ah I see witch it.

This is my rarest but it's a small part that nobody plays of a niche game.
0.2% - American Truck Simulator
Shining Star
Obtain 3 stars in any 3 scenarios played in a row in Truck Driving Proficiency (Driving Academy)
The one I'm proud of:
0.3% - Halo: Master Chief Collection
A Preference for Pain
Halo 3: Complete the Halo 3 LASO Campaign playlist.
All my latest most rare achievements are all from Megabonk, which IMO don't really count. They are easy to get if you just play long enough.
My rarest for a very long time was this one with something like 0.3%, but it has apparently since gone way up. It used to have one of those gold borders around it indicating it was very rare. I got this on my second round that I played and then quit pretty much right after that. Not a very good game, unfortunately.

The one I am most proud of is this one:

I got bored after I took over Britannia as the Britons and had no more enemies who could realistically challenge me, so I sailed directly down to Rome with my army of slingers and tribesmen and sacked Rome for something like 100k denarii.
EDIT: Well, nevermind, this is my newest rare achievement (for now)

It's not so rare now; but on the second day Silksong was out, I got the achievement for defeating Phantom when it was still 0.1%
Divinity: Original Sin 2
A friend and I managed to finish the honour run in less then 10 tries. It was awesome at the end. I played as Sebille and he as the red prince.

I don't have it on Steam yet, but I have Balatro's Completionist++ on mobile.

I'm working on getting it on Steam too. Once you've done it once, getting it again isn't hard, just time-consuming. It's a 0.2% achievement, I think.
Every device I own eventually becomes a Balatro machine.
Phone? Balatro Machine. Steamdeck? Balatro Machine. Work Laptop I can't install programs on? Oh, look at that. Another Balatro machine.