SCP-073 is an Euclid class humanoid anomaly that calls itself “Cain”

SCP-312 is an Euclid class anomaly that appears as a large jellyfish floating in the sky

SCP-058 is a Keter class anomaly, that resembles the heart of a cow.

SCP-087 is a Euclid class anomaly, appearing as a staircase that seems to go forever downwards.

This is a summary of the SCP Foundation workings, such as object class, clearance level, and personal classifications