So far this idea is kinda meh. It's a magnetic sphere, that pulls things around itself, like regular magnets and may be hostile. I'll offer a few suggestions to make this concept a little varied.
1. It's an advanced form of anomalous artificial life, that uses magnetism to form a body and speak to other entities. It could be the only one, or simply one of many. They could have been intended as weapons, infiltrators etc. This would be a Euclid level threat as its origins and motives aren't fully understood.
2. It's an anomalous form of life, that naturally/unnaturally occurred. It's main body/core is a hardened sphere that is incredibly resistant to damage. It is intelligent, like a person, being a silicon based creature, that seeks to grow and reproduce. The real danger it poses, is its potential to replace mankind as a dominant species, much like SCP-1000. This would be a Keter level threat, due to the potential of this SCP to threaten and displace mankind.
3. The SCP could be a form of alien life, that arrived on Earth via meteor impact. It's been trapped underground, slowly pulling material together until it had enough metal to form a body and dig itself free. The entity is primitive in nature, and pulls other metallic objects to itself to form a body. The only way to stop and slow its growth has been to box it in, using non-magnetic materials. - Depending on how big or dangerous it is, this could be a Euclid or Keter class threat.
I'm most fond of idea 2, as I feel that has a lot of story potential here. Idea 1 is also one I like, for this SCP.
