The Gate Guardian is a Euclid/Keter class humanoid entity. It can be viewed as one of the overarching protagonists of the entire mythos. SCP-001 is the being that prompted the creation of the SCP Foundation. He said one word that echoed through the administrator's head, prepare. It was that one word that made the administrator create the Foundation for an unknown future event and to contain many other dangerous or helpful entities and anomaly. It has never left his stations. Not a Hostile Entity