Half Baked Idea - The Demon Core

In my last post, I mentioned a device called the demon core. I know what it looks like, I know that it seethes with power. It is wildly dangerous. 

Aside from that, I know nothing. There was a real device called the demon core. It was 3.5 inch, subcritical mass of plutonium used for testing. In this capacity, it killed two scientists.

Nasty stuff. I may have to revisit this item and flesh it out for use in my campaign.