- last post: 01.01.0001 12:00 AM PDT
I'm pretty sure they've been answered, but I'll answer the first one 'cause it's easy:
The Underground is for discussing anything Bungie, excluding the Website itself. This includes non-Halo games, swag, and such. The Septagon is a forum built for the Website itself. Suggestions and such.
[Edited on 8/22/2006]