Following on from Which Call of Cthulhu books do I need to get started?Which Call of Cthulhu books do I need to get started?, I would also like to get into Delta Green.
Similar questions, then:
- How useful will the core book be on its own?
- Are any other books essential? If so, which?
- Are there any non-essential, but particularly good, books that you'd recommend?
Since I'm familiar with Call of Cthulhu, it would also help me if you could explain how Delta Green differs from it.