Thanks for the ask! And for the first thing I could think of is a Yautja vs SCP-682! I'll include some other SCPs at the end but anyway, here you go!

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•We all know Yautja take trophies after their hunts, well imagine their surprise when they find out this lizard monster thing can heal and can't die.

•Surprised, curious - gotta know more. Quickly they pick more and more interest in this reprtile. Would try to tire it out and observe 682 throughout it all.

•How they came to meet one another is either in the lab or when 682 breaches containment and goes on a walk around the city/forest.

•I do imagine a lot of fighting would break out and even some casualties before the Yautja would retreat with a sample of 682's blood.

•We all know the Upgrade Predator, add to that 682's abilities. :)))) Now we're all screwed.

•An encounter with 999 would be a funny one I imagine. Adorable one too I dare say 😤

•At first a Yautja would be cautious when seeing this jellyfish-on-land approach them, some Yautja would be a bit hostile which would make 999 back off and start shaking.

•At that more curiosity would probably arise, not just because of the jellyfish apperance (from so much travel Yautja's do they probably saw all kinds of species) but also because of its behavior.

•Young Bloods would certainly try and touch it and when they do- BOOM. A purring mess.

•Catch your alien buddy out there purring and just petting or carrying 999

•Elders would be suspicious tho, or any more experienced Yautja. Definitely wouldn't let it approach them so easily or approach them at all.

•If an Elder finds themselves in this euphoric state after coming in contact with SCP-999 they would easily back up, what if this is a trick from this little thing and they are being lead into a trap??

•Nope, not happening.

•More hostile Yautja(say Bad Bloods) would try to kill poor 999 :( so-

•When it comes to the mask I believe none of the Yautja would easily be swayed by it. Not at all really, even the younger ones would know the way this mask is calling to them is a red flag.

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Hopefully this is alright! I'm in a bit of an writers block too so this is all I could think off.

Feel free to request anything more, you can even ask about my own OCs if there is anything that interests you ^^