
Which SCP's can only exist in one canon?
An example i can think of is SCP-4514 Which is an switch-blade that causes well... Death. It's an part of the End of Death canon where an ΩK-Class ("End-of-Death") Scenario happens. Which basically forces immortality on all life.
Due to how normalcy has shifted due to this scenario. It's understandable how this knife would be classified as an anomaly. In any other canon this would just be a regular switch-blade.
What are some other interesting examples of this?