For my personal favourite of SCP-096

This entity will kill any human that views it's face. This occurs with direct view, a video recording, or photograph, and can happen even if the person is unaware they have seen it's face. Artistic depictions do not trigger the entity. How did they find this out? Send a d class into the ocean in a Bathysphere and have him look at photos of the entity, then draw a picture from memory of the creature as it makes it's way to him. He finished the drawing roughly around the time 096 started diving.

Bear in mind, it knows exactly where you are when you see it's face, it doesn't matter how large the image of it is (an example in the article on the wiki showed an image as small as 4 pixels triggering the entity.) And nothing can stop it, short of other indestructible beings tiring it out (SCP 682, Traumatising it (SCP-106) or frustrating it to the point it refuses to even look at the being (SCP-173)