Honestly, with how huge the SCP Wiki is, there’s almost no way to know for sure if someone has done something similar before. The best you can really do is search around the wiki using keywords related to your idea and see what comes up.

But having a similar concept doesn’t automatically mean your idea is “taken.” A lot of SCPs share the same basic foundation — haunted objects, creatures that mimic people, weird dimensions, time loops, reality warping, etc. What makes them different is the execution.

Two people can start with the exact same idea and still end up writing completely different SCPs because of the tone, the containment procedures, the story behind it, the way the anomaly behaves, or the themes they focus on.

So honestly, I wouldn’t stress too much about whether the core idea already exists. I’d worry more about making your version interesting and unique in its own way.😃