Good SCPs for Gaming People - SCP 002 - 299
SCP 002 - SCP 099
SCP-001 is a bit of a meme entry; they kept it intentionally vacant for many years, then held a massive contest to find the best entry. The one they picked is fine but a lot of the alternate-world SCPs I find to be, while interesting, not in the sweet spot of SCP's strengths. If I ran the zoo I'd move them all to the story section (but I don't.) Anyway SCP-001 doesn't belong with SCP 002-100.
These are Very Early SCPs, often simple, text-only and short. A lot of the "mythos" of SCP has not been written; although a few factions (Global Occult Coalition, Are We Cool Yet? - see The Fifth Dimension below) make their first appearances there's little to discuss yet. This makes these early SCPs highly suggestive and very good for exploratory/open-ended gaming.
Now that I've put this together I realize this is a pretty good way for you to understand what I like about the SCP project. If it's strange, frightening, dangerous, perhaps a little silly or surreal, and described bureaucratically, that's a good SCP, to me (not coincidentally these are also the best for gaming because they're the most open-ended).
I should note that I'm curating these for gaming people, not necessarily for gaming directly. As you can see, some of these are very open-ended, others are more like oddly-formatted short fiction with a beginning, middle and end. Ripe for adaptation, perhaps, but not necessarily easy to just directly import. These are the ones I consider to have just the right combination of imagination, missing pieces, fun, the roughness of amateur-created writing, and the polish of easy digestibility. Also that strange feeling when you read something and think "this could make a good scenario."
Finally, there are some SCPs that have puzzle or game elements themselves (though this becomes more common later in the development of the project.)
You can see what others have written about these in (more or less) fanfic form at: Series 1 Tales.
Locations
Items
SCP-092: "The Best of The Fifth Dimension"
Entities
SCP 100 - SCP 199
In these second hundred SCPs, we see the development of new areas of SCP worldbuilding (Marshall, Carter and Dark, and one of my favorites, Dr. Wondertainment) as well as an early example of a good medical SCP, SCP 103, the Never-Hungry Man, linked below.
Of the "gore" SCPs, this is one of the few that emphasizes that medical doctors actually do try to treat patients and are concerned about them. Lots of bad SCPs have high body counts just for the sake of high body counts, and portray the SCP foundation as being more or less maniacal; this one rather drily reports a medical team refusing to do what their boss orders them to do to a patient, being forced to do it anyway, and the boss being "court-martialed".
But you can also see the "torture/just do horrible things to test subjects" style even in otherwise pretty good entries - see the Anachronistic TV, which provoked the Foundation to try to torture people with it rather than figure out how the dang thing was making episodes of I Love Lucy that never existed...
Compare to The Painting (SCP-151), (not included below, but a pretty basic SCP), where obviously the real question is how the Painting was made!
I tend to like SCPs that leave people changed or strained rather than dead or mangled. The Variable Coaster is a good example. People ride the coaster for, subjectively, months, but they are there only for three minutes. This approach to horror/fantasy eventually would manifest in some of the SCP wiki's greatest works, the "infohazard" or "memetic" anomalies, which approached the Lovecraftian idea of knowledge or experiences as the horror itself.
Locations
SCP-100 - "Jamaican Joe's Junkyard Jubilee"
SCP-102 - Property of Marshall, Carter and Dark, Ltd.
SCP-176 - Observable Time Loop
Items
SCP-112 - The Variable Coaster
SCP-145 - Anachronistic Television
SCP-174 - Ventriloquist's Dummy
SCP-194 - Thank You For Your Cooperation
Entities
SCP-103 - The Never-Hungry Man
SCP-125 - Contagious Reflection
SCP 200 - SCP 299
This section has the first "monster SCPs" that I really like for gaming. Too many of the monster SCPs are just "they torturekill you if you break rule X" which are less interesting for gaming than you might think. Puzzles make more sense in gaming if they have other stakes. The Tortured Iron Soul (SCP-203, below) is quite dangerous and gruesome but the obvious motivation in interacting with it is to gain new information about it such as its origin and effects. And The Protector (back to back! SCP-204), once you set aside the edginess of "let's use these pedophiles to activate the anomalistic entity" is also really interesting. This edginess sometimes ruins otherwise interesting entries - the phonograph record that causes time to freeze when it skips is primarily tested by killing someone near it, for example. C'mon. Couldn't we think of other things to test with it?
Overall, there's a LOT of good candidates in this range for gaming even though from a project perspective there's not much mythos or worldbuilding going on. I was really surprised how many of these 100 I thought were good! There are still plenty of derivative SCPs (one is just "what if Silent Hill, man"), and much of the project's identity still remains in the future. One notable entry is the first real action-oriented SCP, primarily consisting of transcripts of the special forces of the SCP going into a weird dimension. It's also been updated to modern presentation standards so it's neat!
There's also my first disease SCP - a lot of these are just zombie/rage infections that make people into m m m m m monsters! Gamers already got plenty of monsters, they don't need more. But this one (Base Eleven Disorder, below) is really nice and intriguing. I didn't pick it because it's not really scenario-inducing, but the Dialysis Bracelet (SCP-269) is also a decent "medicalized" SCP, where you "kinda get what it's trying to do" but it's too alien/bizarre to pull it off.
Similarly, Professor William Wordsworth's Collection of Curiosities (linked below) is good because every new animal comes with sketchy/blinkered but quasi-accurate instructions on how to contain and care for each new anomalous creature, which of course is much more valuable (and challenging) than just gunning them down.
Locations
SCP-211 - Paper-Covered Building
SCP-257 - Professor William Woodsworth’s Collection of Curiosities
Items
SCP-232 - Jack Proton's Atomic Zapper
SCP-261 - Pan-Dimensional Vending
SCP-288 - Stepford Engagement Rings
Entities
SCP-254 - Employee of the Month
SCP-255 - Base Eleven Disorder
Special Note
A fully downloadable and interactive SCP is in this range, and it's very cute. An RPGMaker 2003 game, check out SCP 245 - SCP-RPG