@AgentKuga if i remember correctly SCP-2000 is an SCP that the Foundation created or maybe they just found it, i don't remember, but the point is that the foundation knows of all its components and how they work, so in a sense it is also an explained SCP at least within universe, anyway SCP-2000 main function is to deal with K-class end of the world scenarios (that's the one in which humans become extinct, so is not really the end of the world per see, just the end of humanity), hence the name Deus Ex Machina it exist to literally save the day if something were to happen to kill all humans, and is in essence a cloning factory that would remake all humans an other things.
And this cloning factory is hidden somewhere in Yellow Stone Park, the thing has been used at least twice, but there is suspicion that it may be more times, it only produces or re-produces non anomalous humans, so this means that all anomalous humans are either new, or they somehow survived previous K-Class scenarios, and that's the gigs of it.