Hey there! So, I wanna get my nitpicks out of the way first.

Nitpicks – hide block Object Class: Safe Euclid I like the idea of sentient animals being able to get categorized as Safe; however, the general consensus of all living things as Euclid is just validated by this particular SCP's addendum. The idea that all sentient beings will always be searching for an escape is the basis of the consensus and makes the strikethrough superfluous. Just have it Euclid, if you ask me. The nearest cliff to Site-██ must be maintained to stay at a little above 20 meters at all times and proper cushioning in place at the bottom. Please don't have things redacted in the containment. If you aren't sure of what Site, then just pick one. It isn't as if it's that important.

"A little above" isn't really clinical either. If the height is really important, then there should be some specificity.

Okay, onto some real talk. I like this. It's succinct, simple to get, and straight to the point. Although, it is to a fault, in my opinion. The way you've outlined and written the piece, I feel myself waiting for a final punch, and not really getting one. You have the set-up, the ba-dum-bum without a satisfying tshh.

The idea, I don't want to say lacks originality, but it's extremely in-your-face almost the entire time. When something is that apparent, I kind of expected a little turn-around. If you gave the lemming some sort of alternate ability, or maybe just an unexpected circumstance in the final addendum, you could really liven this up.

All in all, I'd say you need quite a bit more to it. You mention the deaths, then state why it's Euclid, and it leaves me wanting. Try to think less about the effects, and more on the rise and fall of the article.