A collection of interlinked rooms on Habbo Hotel constructed in the early days of raiding. Primarily used for planning, discussion and practice and as regroup and clone-loading areas during raids. Most contain at least a few pieces of furni either scammed or donated from habbofags, or stolen from phished accounts. During the time HQs were in use, the network grew to a rather large size. By the time November 5th, 2006 /B/andetta raid arrived however, the Pool's Closed website was stable and growing and the HQs on Habbo were soon abandoned as unnecessary distractions. You can still find some of theyse HQs if you search for "nigra" on the search tool in the guest rooms.
The network remains intact to this day. All the rooms can be accessed through teleporters, though it can be a complex trip. Due to the original accounts being abandoned or perm-b&, or the rooms are just forgotten, it will probably exist indefinitely for historical purposes and as a decoy for habbofags. Creating new HQs is now major fail and is a sign of either being a habbofag spy or the misguided leader of an afro group. Current fake nigra groups made of fail include The Black Panthers and The Revolution. These should be avoided at all cost due to their habbofaggotry.
Today they obviously play much less of a role, if none at all, because of IRC, image-boards (previously forums), and other services that us nigras run. Nigra HQs are used today (if at all) just to see the numbers of raiders (if it's a small raid) before actually moving on, or to plan an "attack" if you are low on numbers and you need to.