The SCP Foundation (AKA Secure Contain Protect) contains multiple anomalies, ranging from three classes Safe which is the easiest to keep contain, Euclid which is the medium difficultly of keeping contained. Keter is the hardest to keep contained. SCPs are classified by how hard is it to contain not by hostile it is. For example: the nicest anomaly can be classified Keter if it is near impossible to contain.